CBETA: First Multipass Superconducting Linear Accelerator with Energy Recovery

Energy recovery has been achieved in a multipass linear accelerator, demonstrating a technology for more compact particle accelerators operating at higher currents and reduced energy consumption. Energy delivered to the beam during the first four passes through the accelerating structure was recovered during four subsequent decelerating passes. High-energy efficiency was achieved by the use of superconducting accelerating cavities and permanent magnets. The fixed-field alternating-gradient optical system used for the return loop successfully transported electron bunches of 42, 78, 114, and 150 MeV in a common vacuum chamber. This new kind of accelerator, an eight-pass energy recovery linac, has the potential to accelerate much higher current than existing linear accelerators while maintaining small beam dimensions and consuming much less energy per electron.

Prediction of low-frequency structure-borne sound in concrete structures using the finite-difference time-domain method

Due to limitations of computers, prediction of structure-borne sound remains difficult for large-scale problems. Herein a prediction method for low-frequency structure-borne sound transmissions on concrete structures using the finite-difference time-domain scheme is proposed. The target structure is modeled as a composition of multiple plate elements to reduce the dimensions of the simulated vibration field from three-dimensional discretization by solid elements to two-dimensional discretization. This scheme reduces both the calculation time and the amount of required memory. To validate the proposed method, the vibration characteristics using the numerical results of the proposed scheme are compared to those measured for a two-level concrete structure. Comparison of the measured and simulated results suggests that the proposed method can be used to simulate real-scale structures.

Spatial distribution of hexabromocyclododecanes (HBCDs), polybrominated diphenyl ethers (PBDEs) and organochlorines in bivalves from Japanese coastal waters

In order to elucidate the spatial distribution of brominated flame retardants (BFRs) in the Japanese coastal environment, hexabromocyclododecanes (HBCDs), polybrominated diphenyl ethers (PBDEs) and organochlorines (OCs: PCBs, DDTs, CHLs, HCHs, HCB) were determined in bivalves (oysters and mussels) collected from Japanese coastal waters. HBCDs and PBDEs were detected in all samples analyzed. Concentration ranges of HBCDs were 12-5200 ng g(-1) lipid wt., followed by PCBs (20-3100 ng g(-1))>PBDEs (3.1-86 ng g(-1) lipid wt.). The highest concentration of HBCDs was found in the Osaka region. This result indicates that HBCDs are ubiquitous and predominant compounds in bivalves from the Japanese coastal waters. Since no species differences between oysters and mussels were observed for the bioaccumulation properties of HBCDs and PBDEs, oysters could be utilized for BFR contamination monitoring worldwide as an alternative to mussels. Global comparisons between oysters and mussels showed that HBCD concentrations in Japan are among the highest levels reported from Asia and Europe. Estimated dietary exposures of HBCDs and PBDEs through seafood were 0.45-34 ng kg body weight(-1)d(-1), and 0.054-6.8 ng kg body weight(-1)d(-1), respectively. These exposure levels were more than 1000 times lower than the lowest observable effects or no observable adverse effects levels for HBCDs and PBDEs, respectively.

Fluorescence studies on binding of pyrene and its derivatives to humic acid

Binding of pyrene (PyH) and its derivatives to humic acid (HA) has been studied by fluorescence spectroscopy. The nature of the interaction between HA and pyrene derivatives are extensively investigated by employing three derivatives ranging from anionic to cationic compounds: 1-pyrenebutylic acid (PyA), 1-pyrenemethanol (PyM), and 1-pyrenebutyltrimethylammonium bromide (PyB). Binding constants between HA and PyX (X=H, A, M, B) are obtained by steady-state fluorescence quenching techniques, and it is found that PyB has a markedly large binding constant among the pyrene family. This is attributed to a strong electrostatic interaction between cationic PyB and anionic HA. The result suggests that an electrostatic interaction plays a dominant role in binding of pyrenes to humic acid. The importance of electrostatic interaction was also confirmed by a salt effect on the binding constant. Influence of collisional quenching on the binding constant, which causes overestimation of the binding constant, was examined by time-resolved fluorescence spectroscopy as well as temperature effect in steady-state fluorescence measurements. It is elucidated that collisional quenching does not much bring overestimation into the binding constants.

WT1 expression level and clinical factors in multiple myeloma

Although Wilm's Tuomor gene (WT1) was first identified as a tumor suppressor gene for Wilm's tumor, WT1 overexpression has been detected in different malignant cell types including leukemia. Increased expression of WT1 in acute leukemia is potentially used as a marker of minimal residual disease. However, the significance of the gene for multiple myeloma is still not clear. To determine the clinical relevance of WT1 expression in multiple myeloma, we examined the association of clinical parameters and WT1 expression in bone marrow for 17 newly diagnosed multiple myeloma patients. WT1 was assessed by real-time quantitative polymerase chain reaction (RQ-PCR) and calculated standardized WT1 expression level per 100 plasma cells in the bone marrow specimen as "corrected WT1". The expression of standardized WT1 and corrected WT1 in myeloma was 59 to 1,600 copies/microg RNA and 0.05 to 406.3 copies/microg RNA/100 plasma cells, respectively, lower than in leukemia. WT1 transcripts increased when clinical factors worsen, including the stage, amount of M protein, Hb, platelet count, blood urea nitrogen (BUN), creatinine, serum alkaline phosphatase (ALP), calcium, beta2-microglobulin, thymidine kinase activity (TK), and C-reactive protein (CRP). In conclusion, the expression level of WT1 could be an additional marker to the standard parameters considered in risk assessment for multiple myeloma.

Effect of localization of missense mutations in SCN1A on epilepsy phenotype severity

BACKGROUND AND METHODS

Many missense mutations in the voltage-gated sodium channel subunit gene SCN1A were identified in patients with generalized epilepsy with febrile seizures plus (GEFS+) and severe myoclonic epilepsy of infancy (SMEI), although GEFS+ is distinct from SMEI in terms of clinical symptoms, severity, prognosis, and responses to antiepileptic drugs. The authors analyzed the localization of missense mutations in SCN1A identified in patients with GEFS+ and SMEI to clarify the phenotype-genotype relationships.

RESULTS

Mutations in SMEI occurred more frequently in the "pore" regions of SCN1A than did those in GEFS+. These SMEI mutations in the "pore" regions were more strongly associated than mutations in other regions with the presence of ataxia and tendency to early onset of disease. The possibility of participation of ion selectivity dysfunction of the channel in the pathogenesis of SMEI was suggested by a mutation in the pore region (R946C) identified in a SMEI patient.

CONCLUSIONS

There was a significant phenotype-genotype relationship in generalized epilepsy with febrile seizures plus and severe myoclonic epilepsy of infancy with SCN1A missense mutations. More severe sodium channel dysfunctions including abnormal ion selectivity that are caused by mutations in the pore regions may be involved in the pathogenesis of SMEI.

Autoantibodies to NMDA receptor in patients with chronic forms of epilepsia partialis continua

BACKGROUND

Antibody-mediated and cytotoxic T cell-mediated pathogenicity have been implicated as the autoimmune pathophysiologic mechanisms in Rasmussen's encephalitis.

METHODS

The authors investigated autoantibodies against the NMDA glutamate receptor (GluR) epsilon2 subunit and their epitopes in serum and CSF samples from 15 patients with chronic epilepsia partialis continua (EPC), 17 with West syndrome, 10 with Lennox-Gastaut syndrome, and 11 control subjects.

RESULTS

In 15 patients with chronic EPC, we detected NMDA-type GluR epsilon2 autoantibodies in histologically proven Rasmussen's encephalitis (3/3 patients), clinical Rasmussen's encephalitis (6/7 patients), acute encephalitis/encephalopathy (2/3 patients), and nonprogressive EPC (2/2 patients). Serum IgM autoantibodies were found in the early phase of EPC and became negative later in four patients. The autoantibodies were not detected in West syndrome, Lennox-Gastaut syndrome, or controls. Among 10 patients with histologically proven or clinical Rasmussen's encephalitis, epitope analyses showed that the autoantibodies were predominantly against C-terminal epitopes and rarely against N-terminal epitope, with inconsistency in profile during the courses of disease. Epitope recognition spectrum of autoantibodies was broader in CSF than in serum, and the serum or CSF profile showed an increase in number of epitopes as disease progressed in some patients.

CONCLUSIONS

The presence of autoantibodies against NMDA GluR epsilon2 suggests autoimmune pathologic mechanisms but is not a hallmark of Rasmussen's encephalitis. Patients with Rasmussen's encephalitis may have autoantibodies against several neural molecules, and these autoantibodies may be produced in the CNS after cytotoxic T cell-mediated neuronal damage.

Enhanced oxidative damage induced by total body irradiation in mice fed a low protein diet

PURPOSE

To examine the influence of the level of dietary protein on oxidative damage to lipid and protein in the liver and on chromosomal damage in the bone marrow after total body irradiation (TBI).

MATERIALS AND METHODS

Male mice were fed a low (7%), basal (20%) or high (33%) protein diet for 3 weeks, and then received TBI at a dose of 0, 0.5 or 1 Gy. Chromosomal damage in the bone marrow was evaluated by determining the proportion of micronucleated reticulocytes in peripheral blood. Oxidative damage in the liver and plasma, and chromosomal damage in the bone marrow were evaluated on day 2 after TBI.

RESULTS

The levels of lipid peroxides and protein carbonyls in the liver, lipid peroxides in the plasma, and chromosomal damage in the bone marrow, did not differ among the groups that did not receive TBI. However, the oxidative damage to lipid and protein in the liver, and the level of lipid peroxides in the plasma were increased by TBI only in the low protein group. Chromosomal damage in the bone marrow was increased by TBI in a dose-dependent manner, and the damage was consistently higher in the low protein group than in the basal and high protein groups. In the low protein group, a greater decrease of the relative spleen weight by TBI was also observed. The concentrations of antioxidants (vitamin C, E and GSH) in the liver were lower, and the concentration of non-heme iron in the liver was higher in the low protein group than in the basal and high protein groups. The TBI-induced increase in the level of plasma iron was greater in the low protein group.

CONCLUSIONS

Mice fed a low protein diet became susceptible to TBI-induced oxidative damage, and a decrease in antioxidants and an increase in iron are involved in the mechanism of this susceptibility.

Low-dose ACTH therapy for West syndrome: initial effects and long-term outcome

BACKGROUND

Most Japanese pediatric neurologists attempt other treatments before using adrenocorticotropic hormone (ACTH) therapy for West syndrome (WS), and even then, they use only a low-dose synthetic ACTH to avoid serious adverse effects. In this multi-institutional study, the authors analyzed the initial effects, adverse effects, and long-term outcome in patients treated with low-dose synthetic ACTH in Japan.

METHODS

The medical records of 138 patients with WS, who were treated with low-dose synthetic ACTH therapy for the first time at the authors' institutions between 1989 and 1998, were analyzed.

RESULTS

At the end of ACTH therapy, excellent effect on seizures was noted in 106 of 138 (76%) patients, good effect in 23 (17%), and poor effect in 9 (7%). Initial effects on EEG were excellent in 53 of 138 (38%) patients, good in 76 (55%), and poor in 9 (7%). As for seizure prognosis at the time of follow-up, 51 of 99 (52%) patients were seizure-free, whereas 48 (48%) patients had seizures. Mental outcome was normal in 6 of 98 (6%) patients, mild mental retardation in 16 (16%), moderate mental retardation in 26 (27%), and severe mental retardation in 50 (51%). The initial effects of ACTH on seizures and long-term outcome were not dose dependent (daily dosage 0.005 to 0.032 mg/kg, 0.2 to 1.28 IU/kg; total dosage 0.1 to 0.87 mg/kg, 4 to 34.8 IU/kg). The severity of adverse effects correlated with total dosage of ACTH, and the severity of brain volume loss due to ACTH correlated well with the daily dosage and total dosage of ACTH.

CONCLUSION

Low-dose synthetic ACTH therapy is as effective for the treatment of WS as the higher doses used in previous studies. The dosage of synthetic ACTH used in the treatment of WS can be decreased as much as possible to avoid serious adverse effects.

[Relationship between the fecal mutagenicity and metal content, smoking habit and dietary intake]

OBJECTIVE

The study was carried out to collect basic data on exposure of mucous cells of the large intestine to mutagens by investigating the genotoxicity of fecal samples from the urban population. Simultaneously, relations with food intake (food groups and nutritive components), lifestyle factors and fecal metal content was investigated.

METHODS

A total of 199 self-collected fecal samples from middle aged healthy volunteer living in urban areas of Osaka city were freeze-dried and ground in a mill. The mutagenicity of aqueous extracts of the ground samples was measured by the umu-test. Metal content of the feces was analysed by atomic absorption spectrophotometlly. On the day previous to the feces collection, the contents of meals were recorded and confirmed by interview with a dietitian. Quantification of nutritive components was carried out using the 4th edition of the Japan Food Standard Vomposition Table.

RESULTS

Mutagenicity of feces was higher in males than in females, and in those aged 40-49 years than 50-69 years in males but not females. Large differences were found for content of 8 metals in the feces; concentrations were in the decreasing order of calcium, potassium, magnesium, sodium, zinc, iron, manganese and copper, the highest being 20.4 mg for calcium and the lowest was 53.5 micrograms for copper. Between the metal contents and mutagenicity, values for zinc and iron showed positive correlations and for sodium a negative correlation under S9(+) conditions. A weak but significant correlation was observed between the numbers of cigarettes smoked per day and S9 (+) mutagenicity. However we could not find any relation with food groups or nutritive components.

CONCLUSION

It is well known that human feces contain many mutagens and carcinogens and that these can act directly on the mucous membrane of large intestine. Therefore, it is very important to estimate exposure levels. From the present data we can conclude that relations between mutation-activity of the feces and diet are complex. Their elucidation will require a large number of volunteers who have similar living conditions to obtain appropriate data.

[Seizure and developmental prognosis of West syndrome--combination therapy with high-dose vitamin B6, valproate and low-dose ACTH]

Twenty patients with West syndrome were initially treated with high-dose vitamin B6 (40 to 50 mg/kg/day) and valproate (40 to 50 mg/kg/day). Three became seizure free. For the remaining 17 patients, low-dose synthetic ACTH (0.01 mg [0.4 IU]/kg/day) was added to the regimen. One month after the end of ACTH therapy, 13 patients were seizure free. Thus 16 patients in total(80%) were free of seizures(group A). The treatment was ineffective for the remaining 4 patients (20%; group B). During the following for a mean period of 64 months (range, 48 to 83 months), 9 in group A had a relapse of epileptic seizures. However, only 4 in this group had epileptic seizures at the end of the study (5-7 years of age), all of which were partial and infrequent. In group B, two had frequent intractable seizures, and one was seizure free at the end of the study. One died at the age of 1 year. In group A, 2 patients showed normal or subnormal mental development. Mild, moderate and severe mental retardation were seen in 3, 4 and 7 patients respectively. In group B, all patients showed severe mental retardation. In this study, the rate of evolution into intractable epilepsy was low, but long-term mental development was poor. Seizure control by itself seemed to be insufficient to improve long developmental prognosis of West syndrome.

Different effects between 7-nitroindazole and L-NAME on cerebral hemodynamics and hippocampal lesions during kainic acid-induced seizures in newborn rabbits

We examined the effects of 7-nitroindazole (7-NI) and N-omega-nitro-L-arginine methyl ester (L-NAME) on the endogenous nitric oxide (NO) production in vivo, cerebral hemodynamics, and hippocampal lesions to investigate the different roles between endothelial NOS (eNOS) and neuronal NOS (nNOS) during kainic acid (KA)-induced seizures in newborn rabbits. After a pre-treatment with 7-NI (50 mg/kg, i.p.), L-NAME (20 mg/kg, i.v.) or saline (1 ml, i.v.), KA (12 mg/kg, i.v.) was administered. NO production in the brain, regional cerebral blood flow (rCBF), cerebral oxygenation (concentrations of oxyhemoglobin (HbO2), deoxyhemoglobin (HbR), and total hemoglobin (tHb) in the brain tissue), and electroencephalography (EEG) were continuously monitored throughout the experiment lasting at least 60 min after the KA administration. There was a significant increase in NO generation in the brain during KA-induced seizures, which was inhibited by a pre-treatment with 7-NI or L-NAME. KA-induced seizures also increased rCBF significantly, which was inhibited not by 7-NI but by L-NAME. L-NAME pre-treatment caused a significant decrease in HbO2 and a significant increase in HbR during KA-induced seizures, compared with 7-NI and saline pre-treatment. EEG abnormalities and Neuronal damages in the hippocampus were significantly lower in 7-NI- and L-NAME-treated animals respectively, than in saline-treated animals. The present data demonstrated that the selective nNOS inhibitor, 7-NI, attenuated neither rCBF nor cerebral oxygenation during the seizures, while the non-selective NOS (nNOS and eNOS) inhibitor, L-NAME, attenuated both. These findings suggest that NO, probably originating from eNOS, may play an important role in the cerebral circulation. Both 7-NI and L-NAME inhibited the NO production and EEG abnormalities during the seizures that led to less damage to the hippocampus.

Effects of eicosapentaenoic acid on blood pressure, cell membrane fatty acids, and intracellular sodium concentration in essential hypertension

This study was designed to clarify the effects of orally administered eicosapentaenoic acid (EPA) on blood pressure, intracellular sodium content, and cell membrane fatty acid composition in patients with essential hypertension. After a 4-week run-in period, a study group of 17 male patients was assigned to an 8-week treatment with EPA (2.7 g/day) or placebo in a randomized, double-blind fashion with a crossover at week 4. Systolic blood pressure (SBP) was lower after treatment with EPA than after treatment with placebo (152.9+/-17.3 vs. 162.6+/-20.6 mmHg; p<0.01), while diastolic blood pressure was not statistically different. Compared with the placebo treatment, EPA supplementation resulted in a decrease in intraerythrocyte sodium content (R-Na; 11.17+/-0.63 vs. 10.44+/-1.28 nmol/l cells; p<0.05) accompanied by an increase (p<0.001) in erythrocyte membrane EPA content. The increase in membrane EPA content was related to the decrease in SBP (r=-0.52, p<0.05) and the decrease in R-Na (r=-0.57, p<0.02) during EPA treatment. The decrease in R-Na correlated positively with the decrease in SBP (r=0.54, p<0.05), and correlated negatively with the change in Na+-K+ ATPase activity (r= -0.59, p<0.02). However, the change in Na+-K+ ATPase activity did not directly correlate with the change in membrane EPA content. In conclusion, oral EPA supplementation increased membrane EPA content and reduced SBP in patients with essential hypertension. Based on the association between the increase in membrane EPA content and the decrease in intracellular sodium concentration, EPA may lower blood pressure by altering the activities of the membrane sodium transport systems.

An accurate three-dimensional cephalometric system: a solution for the correction of cephalic malpositioning

In recent years, methods have been developed that calculate three-dimensional (3D) co-ordinates of orthodontic landmarks from lateral and frontal cephalograms. However, precise measurement has been impossible with these methods because, although they corrected the magnification of the image, they did not correct 3D cephalic malpositioning that occurs during the measurement of human subjects. In this study, we developed a 3D cephalometric system that corrected not only for magnification of the image, but also 3D cephalic malpositioning during cephalogram exposure. Magnification of the image was corrected for first. Cephalic revolution was then sequentially corrected and divided into elements of x-, y-, and z-axes. The origin was parallelly translated to the mid-point of bilateral porion. In order to examine the accuracy of this system, seven human dry skulls were measured. The accuracy unaffected by the cephalic revolution in any direction and standard errors was within 0.8 mm in any orthodontic landmarks. It was suggested that this measurement system would have sufficient accuracy for clinical application. The results indicated that precise cephalometric measurement was possible with this system and it was suggested that its clinical application would be possible.

Diagnosis of horizontal enterovirus infections in neonates by nested PCR and direct sequence analysis

A hospital-acquired outbreak with febrile illness and/or rash occurred in our neonatal special care nursery (SCN) from September 1995 to September 1996. A total of 23 infants developed symptoms. We could not detect the etiological agents by routine virus isolation. In a retrospective study, however, enterovirus RNA was detected by reverse transcriptase-polymerase chain reaction (RT-PCR) from four out of six cerebrospinal fluid (CSF) samples and from two of 12 sera. Thus six out of 16 patients from whom samples were obtained were diagnosed retrospectively as having enterovirus infection. Furthermore, we detected the enterovirus genome from four of 20 serum samples obtained from patients who had other clinical symptoms, and from infants hospitalized without noticeable clinical illness during the same periods. This outbreak was caused by two different enteroviruses, which we assumed were echovirus type 7 (Echo 7) and coxsackievirus B3 (Cox B3), because of the sequence results. We demonstrated the clinical advantage of the analysis of nucleotide sequencing as supportive evidence of transmission.

[Evaluation of hematopoiesis by granulocyte elastase after hematopoietic stem cell transplantation]

To evaluate hematopoietic restoration after hematopoietic stem cell transplantation (HSCT), we sequentially monitored the post-HSCT level of granulocyte elastase (GE), a sensitive parameter of qualitative and quantitative changes in granulopoiesis. We compared it with routinely used hematopoietic recovery indices, such as leukocyte and reticulocyte count. We also compared levels of GE in the clinical administration of different colony stimulating factors (granulocyte-colony stimulating factor (G-CSF) versus macrophage-colony stimulating factor (M-CSF) and in different types of hematopoietic stem cell transplantation (allogeneic bone marrow transplantation (BMT) versus autologus peripheral blood stem cell transplantation (PBSCT)). Days to first increase of GE after HSCT were 3.0 and 2.3 days earlier than increase of leukocytes in allo-BMT and auto-PBSCT, respectively. Recovery of highly fluorescent reticulocytes and monocytes were later than recovery of GE. These results indicated that granulopoiesis after transplantation started before the increase in peripheral leucocyte count, and that GE was the earliest indicator of hematopoietic recovery. On the basis of GE level, M-CSF had the same stimulating effect on granulopoiesis as G-CSF. The nadir of GE in PBSCT was significantly higher than that in BMT, indicating continuous granulopoiesis in PBSCT. From these results, we concluded that measurements of GE can be used for the clinical evaluation of myelosuppression by different conditioning regimens as well as of granulopoiesis induced by various cytokines.

[Analysis of pulmonary function in leukemia patients after bone marrow transplantation: effects of prior chemotherapy]

To evaluate the effects of prior chemotherapy on pulmonary function after bone marrow transplantation(BMT), pulmonary function tests were performed prior to and after BMT on 7 acute leukemia (AL) and 13 chronic myelogenous leukemia (CML) patients given with CY (60 mg/kg x 2 days), total body irradiation (3 Gy x 4 days, 10 cGy/min), and CyA plus short-term MTX. No patient had graft-versus-host disease or lung complications. Pulmonary function after BMT did not deteriorate in the AL patients; however, both %Vital Capacity(%VC) and DL/VA decreased significantly in the CML patients (%VC before BMT: 112.1 +/- 11.5%, after BMT: 93.7 +/- 9.4%; DL/VA before BMT: 79.2 +/- 14.6%, after BMT: 54.1 +/- 10.6%). Although prior regimens of busulfan (BU) or interferon (IFN) were equal risk factors for decreased %VC after BMT, decreases in DV/VA were more significant in CML patients who received IFN. CML patients, especially those who have received BU or IFN, should be carefully monitored for pulmonary function to prevent respiratory failure after BMT.

[Utility and intricacy of molecular diagnosis of spinal muscular atrophy]

To diagnose spinal muscular atrophy (SMA), we examined the deletion of exons 7 and 8 of the survival motor neuron (SMN) gene and exon 5 of the neuronal apoptosis inhibitory protein (NAIP) gene in 7 patients from 6 unrelated families, using the polymerase chain reaction method. Two patients with type I and two with type II SMA had the deletion in SMN, whereas 2 of the 3 patients with type III had no deletion in these genes. Thus, the method was not as useful in type III as in type I and II for making a diagnosis of SMA. Together with the data previously reported by others, our data indicated the possibility that the deletion frequency in type III SMA is lower in Japanese patients (< 40%) than in non-Japanese patients (> 80%). Two siblings had SMA of different severity; the older brother having type III and the younger brother type II. Both had the same deletion in the SMN gene. The different phenotypes in these siblings with the same genotype indicated that caution is required when utilizing molecular data for genetic counseling or prenatal diagnosis of SMA.

Successful management of intractable epilepsy with intravenous lidocain and lidocain tapes

The authors report on the successful management of a 6-year-old male with intractable epilepsy using intravenous lidocaine and lidocaine tapes. At 4 years of age, he developed psychomotor deterioration and intractable epilepsy associated with leukoencephalopathy secondary to the treatment of central nervous system leukemia. His seizures were refractory to conventional antiepileptic drugs. The adjunct treatment with intravenous lidocaine and lidocaine tapes proved effective in controlling the intractable seizures. Mental state and motor activity subsequently began to improve after the reduction of the seizures.

Effects of nitric oxide synthase inhibition on the cerebral circulation and brain damage during kainic acid-induced seizures in newborn rabbits

The nitric oxide (NO) synthase inhibitor, N-omega-nitro-L-arginine methyl ester (L-NAME), was used to investigate the effect of endogenous NO on the cerebral circulation and brain damage during kainic acid (KA)-induced seizures in newborn rabbits. The cerebral blood flow (CBF), by laser doppler flowmetry, cerebral oxygenation (concentrations of oxy-(HbO2), deoxy-(HbR) and total hemoglobin (tHb) in brain tissue), by near-infrared spectroscopy (NIRS), mean arterial blood pressure (MABP), electroencephalography (EEG), and hippocampal neuronal damage were evaluated. Pretreatment with L-NAME caused significant decreases in CBF, HbO2, and tHb, and a significant increase in HbR during KA-induced seizures, compared with pretreatment with saline (P < 0.05), without a significant difference in MABP. Our study also demonstrated that pretreatment with L-NAME reduced the seizure activity and neuronal cell death in the hippocampus elicited by the systemic administration of KA in the neonatal brain. These results suggest that NO is of major importance in the neurodestructive process in spite of its roles in maintaining both the CBF and cerebral oxygenation during KA-induced seizures in the neonatal brain.

Characteristics of the production of active oxygen species from adherent and non-adherent neutrophils

Our objective was to evaluate the characteristics of the production of AOS from the neutrophils that had adhered to the endothelial cells, fibronectin or polystyrene, using the method of electron paramagnetic resonance (EPR) spin trapping. Neutrophils and endothelial cells were isolated from human venous blood and umbilical veins, respectively. AOS production from neutrophils was not elicited only by adhesion. The stimulation of adherent neutrophils with phorbol myristate acetate (PMA) induced the production of AOS. The production of AOS from adherent neutrophils to endothelial cells, but not to fibronectin or polystyrene, decreased with the interval time between the adhesion and the stimulation by PMA. The amount of AOS produced by the neutrophils adherent to fibronectin or polystyrene was maintained for one hour after stimulation with PMA, whereas that by suspended neutrophils gradually decreased with the time after stimulation. Results indicate that adherent and non-adherent neutrophils exhibit differing time course of AOS production.

Inhibition of NF-kappaB, iNOS mRNA, COX2 mRNA, and COX catalytic activity by phenyl-N-tert-butylnitrone (PBN)

Previously, the spin trapping agent phenyl-N-tert-butylnitrone (PBN) has been shown to decrease the level of nitric oxide synthase mRNA in vivo. This inhibition is suggested to be an underlying mechanism for PBN's wide variety of pharmacological actions in animal models. However, the determination of PBN's cellular pharmacological activities has not been carried out, but is necessary for the understanding of the effects in vivo. Since the known pharmacological effects of PBN are primarily anti-inflammatory in nature, in this study we determined the inhibitory activities of PBN against two inflammatory factors: inducible nitric oxide synthase (iNOS) and inducible cyclooxygenase (COX2). We show here that PBN decreases steady state COX2 mRNA level and COX2 catalytic activity in macrophage cell culture at supra-pharmacological concentrations. While PBN decreases iNOS mRNA, it does not inhibit iNOS catalytic activity, which is consistent with previous in vivo studies. We also studied nuclear factor kappaB (NF-kappaB), a transcription factor that can rapidly activate the expression of genes involved in inflammatory, immune and acute phase responses. The binding of NF-kappaB to iNOS gene has been shown to be critical for iNOS gene expression, and the promoter region of COX2 gene contains NF-kappaB consensus sequence. We show that PBN inhibits lipopolysaccharide-mediated increase of NF-kappaB DNA binding activity with a lower concentration than that for the non-steroidal anti-inflammatory drug (NSAID), salicylate. Furthermore, we show that PBN inhibits COX2 catalytic activity, suggesting that PBN has an NSAID-like function.

[Pulmonary function at the early stage after bone marrow transplantation]

Twenty-one patients, aged 16-41 years, were prospectively followed for pulmonary function prior to and up to nine months after bone marrow transplantation (BMT). All patients had normal radiographs and no clinical signs of pulmonary disease. The FEV1.0%, V25, and of V50/V25 were within the normal ranges for all patients. Percent vital capacity (%VC) and percent diffusing capacity of lung for CO (% DLco) dropped progressively in most of the patients up to 9 months following BMT. Pulmonary function decreased earlier in patients with GVHD as well as patients who received total body irradiation either at a high dose rate (10 cGy/min) or a high lung dose (12 Gy). These asymptomatic declines in pulmonary function were measured by frequent tests of lung function.

Usefulness of nested PCR and sequence analysis in a nosocomial outbreak of neonatal enterovirus infection

BACKGROUND

Non-polio enterovirus infections are recognized in children during summer-fall seasons and they sometimes cause large outbreaks. We experienced a nosocomial infection in the neonatal nursery and echovirus type 7 was isolated from samples of four patients.

OBJECTIVES

We diagnosed the horizontal infection of four neonates by reverse transcriptase-nested polymerase chain reaction (RT-nested PCR) and the nucleotide sequence.

STUDY DESIGN

Total RNA was extracted from clinical isolates, serum samples and cerebrospinal fluid (CSF). We amplified enterovirus genome in the 5'-noncoding region by nested PCR and determined the nucleotide sequences.

RESULTS

Enterovirus genome was detected in all isolates, in the acute-phase sera in all four patients and in the CSF in one patient by the first PCR. By using nested PCR, the genome was detected from convalescent-phase sera in two patients. All enterovirus genome obtained from the nursery outbreak showed the same sequences with 100% homology.

CONCLUSION

We demonstrated the clinical advantages of RT-nested PCR from serum samples and the analysis of nucleotide sequencing gave the supportive evidence of identification of transmission pathway.

[A case of multiple sclerosis with initial symptoms of narcolepsy]

We reported a 13-year-old boy diagnosed as multiple sclerosis associated with narcolepsy. He had suffered from retrobulbar optic neuritis at the age of 11 years which was improved gradually by prednisolone. Four months later he was admitted because of excessive somnolence. The diagnosis of narcolepsy was made based on hypnagogic hallucination, sleep paralysis, changes of personality and the sleep onset sREM (SOREM). The elevation of anti-measles antibody and a positive oligoclonal band in CSF, low density areas in the bilateral internal capsule on CT scan, and high signal areas in the same region on T2-weighted MRI confirmed the diagnosis of multiple sclerosis. An abnormal arousal response occurred occasionally in sleep stage 2 and 4, which started with electrical silence followed by a period with irregular high voltage slow waves and repetitive focal spike train. Those clinical symptoms and abnormalities of biochemical and electrophysiological studies normalized after treatment with prednisolone. However, abnormalities on MRI showed no improvement even after long term administration of prednisolone (2.5 mg/day).

[Donor leukocyte transfusion as treatment for relapsed chronic myelogenous leukemia after allogeneic bone marrow transplantation]

Three patients with relapse (two molecular and one cytogenetic relapse) after allogeneic bone marrow transplantation (BMT) for chronic myelogenous leukemia (CML) were treated with donor leukocyte transfusion (DLT). Two had complete molecular remission, which persisted 16 and 20 months after treatment. The performance status of all patients was 90-100%. Mild chronic GVHD was observed in one patient as a side effect of DLT. One patient with cytogenetic relapse required three infusions to attain molecular remission and this suggests the importance of cell numbers to infuse in DLT. Positive anti-nuclear antibody was observed in the effective cases and elevation of IgE in all cases after DLT. These abnormal laboratory findings may suggest a relationship between GVHD and GVL. DLT may be effective therapy for patients with CML who relapse after BMT. Further controlled studies are necessary to determine the optimal number of cells to infuse, interval and frequency of DLT.

Comparative electrophysiologic findings between responders and nonresponders to class III antiarrhythmic drugs among patients with ventricular tachyarrhythmia

Electrophysiologic testing was performed in 31 patients with ventricular tachycardia (21 cases) and fibrillation (10 cases) to characterize the electrophysiologic properties of patients responding or not responding to therapy with class III antiarrhythmic drugs. At the baseline, there were no differences among the patients in the monomorphic VT cycle length (CL), block CL or the width of the zone of entrainment. Ventricular tachyarrhythmias after the administration of class III drugs (sotalol: 9, amiodarone: 15 and E-4031/MS-551: 7) were inducible (non-responders) in 17 patients and non-inducible (responders) in 14 (45%). The class III drugs prolonged the sinus cycle length (SCL), QT interval and right ventricular effective refractory period (VERP), but had little effect on ventricular conduction time in the responders and non-responders. The SCL, QT interval and VERP at the three drive cycle lengths of 600, 400 and 300 msec were significantly longer in the responders than in the non-responders, but the class III drug action on VERP showed a reverse use-dependency. Isoproterenol administered to the responder did not fully reverse the class III antiarrhythmic drug-induced prolongation of QT, QTc and VERP, which remained significantly prolonged compared to the baseline values. Furthermore, when the VERP after the administration of class III drugs were greater than 270, 250 and 240 msec at the three drive cycle lengths of 600, 400 and 300 msec, respectively, it was associated with the non-inducibility of VT/VF. Though the precise mechanism of the drug efficacy is not yet known, these observations help to clarify the ability of class III drugs to prevent the induction of ventricular tachyarrhythmia.

Nephrogenic diabetes insipidus and tethered cord syndrome with a lipoma of the cauda equina

The tethered cord syndrome is characterized by sensory and motor disturbances of the lower extremities and incontinence. We report a 12-year-old girl with a cauda equina lipoma and a tethered spinal cord, whose chief complaints were polyuria and polydipsia. She was diagnosed as having nephrogenic diabetes insipidus. This unusual complication of the tethered cord syndrome was most likely due to a hydronephrosis secondary to a neurogenic bladder. Thus, spinal lesions have to be considered in patients with polyuria and polydipsia.

Analysis of Complexation Equilibria of Polyacrylic Acid by a Donnan-Based Concept

Complexation equilibria of uni- and divalent metal ions (Ag+, Ca2+, Cu2+, and Pb2+) with polyacrylic acid (PAA) have been studied at various degrees of dissociation (alpha) of PAA under different sodium salt concentration levels at 25&deg;C. Both pH and pM(MZ+ = Ag+, Ca2+, Cu2+, and Pb2+) of equilibrium mixture solutions of MZ+/PAA/Na+ (excess) have been determined concurrently by a potentiometric titration method. The electrostatic effect inherent in the polyion-metal ion binding equilibria has been evaluated by a Donnan-based concept and is corrected for by the use of a nonideality term of acid dissociation equilibria of the polyacid as a probe. For Ag+-PAA and Ca2+-PAA bindings, only monodentate ligand complexes, (MA)(Z-1), have proven to be formed, whereas for Cu2+ and Pb2+ ion bindings, formation of both monodentate and bidentate ligand complexes have been observed. For both Cu2+-PAA and Pb2+-PAA systems, bidentate carboxylate complex formation is predominant at alpha > ca. 0.3, whereas at alpha < ca. 0.3, formation of monodentate carboxylate complexes becomes appreciable as alpha decreases. Stability constants of these complexes together with the intra-molecular complexation equilibrium constants expressed by the ratio of the concentrations of bidentate complexes to monodentate complexes have successfully been evaluated and are compared with each other in order to discuss the multidentate complexation properties of the polycarboxylic acid.

Optimal time and dosage of phenyl N-tert-butyl nitrone (PBN) for the inhibition of nitric oxide synthase induction in mice

We have previously reported that phenyl N-tert-butyl nitrone (PBN) inhibits the induction of inducible nitric oxide synthase (iNOS) and, thus, prevents the overproduction of nitric oxide (NO), resulting in the reduction of endotoxin-mediated death in mice. In this study, to examine the effect of PBN in detail, we investigated the dose- and administration-timing dependence of PBN on endotoxin-induced NO generation in mice. NO generation was monitored in the mouse liver after administration of lipopolysaccharide (LPS) by the in vivo NO-spin trapping method using the iron complex of N-methyl-D-glucamine dithiocarbamate (MGD) as a spin trap, followed by ex vivo EPR measurement of the liver tissue. PBN was effective in reducing liver NO generation monitored 6 h after endotoxin injection when it was administered shortly before or after LPS injection. The maximum inhibition of liver NO was obtained when PBN was administered 30 min before LPS injection. ID50 for the inhibition was estimated to be approximately 200 mg/kg when the LPS dose of 50 mg/kg was used. Expression of mRNA for iNOS in the liver as estimated by reverse transcription polymerase chain reaction was decreased when PBN was given 30 min before LPS injection, indicating that the reduction of expression of iNOS protein by PBN, which has been shown previously, is at least in part caused by a decrease in mRNA expression.

On the Complexation of Cd(II) Ions with Polyacrylic Acid

Complexation of Cd(II) ions with polyacrylic acid has been studied potentiometrically and by 113Cd NMR spectroscopy. A Donnan model proposed by Marinsky (Marinsky, J. A., in "Ion Exchange and Solvent Extraction" (J. A. Marinsky and Y. Marcus, Eds.), Vol. 11, p. 237. Dekker, New York, 1993; Miyajima, T., in "Ion Exchange and Solvent Extraction" (J. A. Marinsky and Y. Marcus, Eds.), Vol. 12, p. 275. Dekker, New York, 1995) has been applied in order to correct for the electrostatic effect on the equilibria inherent in the polyelectrolyte nature of the polyions. The potentiometric studies showed that the bidentate ligand complex, (CdA2)0, is the dominant species, but the formation of monodentate ligand complex, (CdA)+, cannot be neglected at low degree of dissociation of the polyacid. The stability constants of the (CdA)+ and (CdA2)0 complexes have been determined to be approximately 3.2 x 10 and 1.6 x 10(2), respectively. These values are in good agreement with the stability constants of 4.1 x 10 and 1.0 x 10(2) for Cd(acetate) and Cd(glutarate) complexes, where acetate and glutarate ions are the monomer analog ligands of polyacrylic acid. The 113Cd NMR chemical shift change upon dissociation of the polyacid also indicates that the dominant complex is (CdA2)0, but (CdA)+ becomes more appreciable with the decreasing degree of dissociation of the polyacid.

Rebamipide protects against activation of neutrophils by Helicobacter pylori

Our objectives were to determine whether rebamipide, a unique antiulcer agent, would inhibit adhesive reactions between neutrophils and endothelial cells as well as the production of active oxygen species from neutrophils elicited by an extract of H. pylori. A water extract of H. pylori that was prepared from biopsy materials obtained from a patient with gastric ulcer increased the surface expression of CD18 on human neutrophils isolated from peripheral blood, the adhesion of neutrophil-endothelial cells, and the production of active oxygen species by neutrophils. Rebamipide, at concentrations of 10(-5) and 10(-6) M, reduced the adherence of neutrophils to endothelial cells as well as the CD18 expression on neutrophils induced by this bacterial extract. Rebamipide also inhibited the production of active oxygen species from neutrophils stimulated by H. pylori extract. These results suggest that rebamipide protects against the gastric mucosal inflammation associated with H. pylori by inhibiting neutrophil function.

A case of intractable epilepsy positive for the detection of measles virus genome in the cerebrospinal fluid and peripheral mononuclear cells using reverse transcriptase-polymerase chain reaction

We report a rare case of intractable frontal lobe epilepsy with mental deterioration, in which the measles virus gene was detected from the cerebrospinal fluid (CSF) and peripheral mononuclear cells (PBMC) obtained 9 years after the first epileptic episode using reverse transcriptase-polymerase chain reaction (RT-PCR). The patient had been immunized with an attenuated measles vaccine and had no history of clinically apparent acute measles infection. However the analysis of the sequence of the PCR product from CSF showed the circulating wild strain genotype at the time when the patient complained of his first epileptic episode.