Ion heating and high-energy-particle production by ion-cyclotron heating in the large helical device

Ion-cyclotron heating was applied to the Large Helical Device. When the proton-cyclotron resonance was near the saddle point of the magnetic field-strength plane, strong ion-cyclotron damping occurred. Under these conditions efficient plasma heating was achieved for more than one minute. A high-energy ion tail was observed, and the effective tail temperature was determined by a balance between the wave acceleration and the electron-drag relaxation. There was no apparent sign of particle orbit loss effect in the investigated density range of 0.8-1.3x10(19) m(-3).

Carcinoma of the pancreas with endocrine component in childhood. A case report.

A case of pancreatic tumor in a six-year-old girl is presented. The tumor had histologic characteristics of acinar cell carcinoma with endocrine component. Grossly, it was encapsulated and attached to the tail of the pancreas, measuring 8 cm in the greatest diameter. Histologically, the tumor was composed of medium-sized tumor cells, with mild pleomorphism showing mainly acinar structures. Many of these tumor cell contained fine granules that were periodic acid-Schiff positive, diastase resistant, and positive with dimethylaminobenzaldehyde nitrite strain for tryptophan, and some contained granules that were positive with Grimelius stain and positive with peroxidase-antiperoxidase technic for gastrin. Electron microscopy revealed two types of membrane-bound granules in the tumor cells. The larger granules measured 400-700 nm in diameter and appeared to be zymogen granules, while the smaller ones measured 100-200 nm in diameter and appeared to be neuroendocrine granules. Some cells contained both granules. The postoperative course of the patient was excellent, and she was alive and well 13 years after operation. This may be the second reported case of acinar-endocrine cell tumor of the pancreas.

Characterization of iris pigment epithelial cell for auto cell transplantation.

To establish auto iris pigment epithelial (IPE) transplantation, we characterized the properties of IPE cells and the method of culture using auto serum. Monkey and human IPE cells were obtained and cultured in several conditions, using auto, mouse, rabbit, bovine, or human serum. Immunocytochemical study was performed to confirm that the cells were epithelial in origin. The proliferation rate of the IPE was also calculated from fresh human IPE cells, which were obtained during filtering glaucoma surgery. Proliferation rate was also compared to that of retinal pigment epithelial (RPE) cells. Reverse-transcriptase and polymerase chain reaction for melanogenesis was performed, and the amount of pigment in the IPE cells was also calculated. Mouse and rabbit sera were not effective for the monkey IPE cell culture. Conversely, the cells grew well in the medium with auto, bovine, or human serum. Human IPE cells grew exponentially by the described methods and reached to 60,000 cells after about 4-5 weeks. When we compared them by proliferation rate, IPE cells were less proliferative than RPE cells. The gene expression for melanogenesis and the amount of pigment in the IPE gradually decreased through successive passages. Transplantation has been tried for the treatment of age-related macular degeneration using RPE from fetus or from eye bank eyes. However, focal rejection may play an important role in the clinical results. The establishment of auto IPE cell transplantation may improve the problem of rejection. In the present study, we established auto IPE cell culture using auto serum. The cultured IPE cell showed pigment epithelial cell properties until around five passages in both human and monkey.

Identification of fatty acid methyl esters in kidneys and livers of two patients with Reye's syndrome.

An unusual lipid, having an Rf value between that of cholesterol ester and of triglyceride on thin-layer chromatography, was clearly demonstrated in lipids from kidneys and livers of two Japenese children with Reye's syndrome. Gas chromatography-mass spectrometry revealed that the unusual lipid from viscera of the patients was a mixture of fatty acid methyl esters. Whether the occurrence of fatty acid methyl ester is the result of an inborn error of metabolism common to both patients, who were the progeny of consanguineous marriages, or whether it is a common biochemical feature in Reye's syndrome remains the subject of future studies.

Intra-arterial digital subtraction angiography for children with idiopathic renal bleeding: a diagnosis of nutcracker phenomenon.

Among children with asymptomatic hematuria, 28 cases of nonglomerular idiopathic renal bleeding were subjected to this series of study. Intra-arterial digital subtraction angiography (DSA) and/or renal venography were performed to investigate the hematuria of unknown etiology. DSA clearly demonstrated the entrapment of the left renal vein (LRV), or nutcracker phenomenon in the majority of our patients (22 out of 28 cases): obstruction of the LRV with well-developed collaterals were found in 8 cases, and in the remaining 14 cases, various degrees of LRV compression were demonstrated. A characteristic real-time DSA image was the congestion of LRV associated with collaterals and/or intermittent venous flow at the compressed segment of LRV. The pullback pressures from LRV to the inferior vena cava (IVC) that were obtained from 5 of these patients demonstrated gradients of 2 mmHg (3 cases), 3 mmHg (1 case), and 5 mmHg (1 case), respectively. The parallel application of ultrasonography has given positive signs for LRV entrapment, although they have not necessarily coincided with the existing criteria of nutcracker phenomenon. Considering the high incidence of LRV entrapment among children with nonglomerular hematuria, most nutcracker phenomenon should be diagnosed on ultrasonography. However, intra-arterial DSA is an important tool to establish the disease entity and ultrasonic criteria.

Endodermal cyst in the cerebellopontine angle with immunohistochemical reactivity for CA19-9.

We present a rare case of the endodermal cyst in the cerebellopontine angle with positive immunohistochemical reactivity for CA19-9. The patient was a 67-year-old woman with an endodermal cyst in the cerebellopontine angle who presented with progressive gait disturbance. A magnetic resonance image showed a cerebellopontine angle which was low in signal on T1-weighted, and high on T2-weighted image without gadolinium enhancement. The preoperative diagnosis was an epidermoid or arachnoid cyst. The patient underwent surgery. Since the intraoperative histological diagnosis by frozen section was endodermal cyst, total removal of the cyst wall was achieved for preventing recurrence. The postoperative definitive histological diagnosis was endodermal cyst, type A by Wilkins-Odom classification, lined by mucinous epithelium with an immunohistochemical reactivity for CA 19-9 protein and cytokeratin. This is the first reported case of a huge endodermal cyst in the cerebellopontine angle of an elderly woman which exclusively showed a differentiation toward the midgut epithelium. The histological diagnosis during surgery by frozen section should be performed for proper treatment.

Cerebellopontine angle meningioma with a high jugular bulb.

A cerebellopontine angle meningioma originating from the skull base over a high jugular bulb is quite rare. We report a case of a 68-year-old woman who had a right cerebellopontine angle meningioma with a prominent high jugular bulb. CT and MRI revealed a round tumour which attached to a bony prominence over the high jugular bulb. The apex of the jugular bulb was 3 mm higher than the floor of the internal auditory canal. The tumour was removed via a suboccipital retrosigmoid approach. The bony projection was drilled off carefully using a diamond drill; the jugular bulb became visible through the thinned bone. When a meningioma of this type is removed including bony changes, special attention is needed to avoid injury to the jugular bulb.

Quantitative analysis of major histocompatibility complex class II-positive cells in posterior segment of Royal College of Surgeons rat eyes.

Potential antigen-presenting cells in the posterior segment of Royal College of Surgeons (RCS) rat eyes were analyzed quantitatively. Light microscopic immunohistochemistry was performed at postnatal days (P) 10, 20, 28, 42, 63, and 140 in the eyes of RCS rats and their congenic counterparts. Immunohistochemical studies were carried out using monoclonal antibodies against major histocompatibility complex (MHC) class II antigen (OX6), a cytoplasmic antigen in bone marrow-derived macrophages (ED1), a membrane antigen on resident tissue macrophages (ED2), and a microglia/macrophage marker (OX42). Some sections were stained by a double-labeling method using these antibodies. No MHC class II-positive cells were seen in dystrophic RCS rat retinas at P10. They were found, however, in the outer nuclear layer and debris of outer segments at P20. From P20 to P42 the number of cells increased, then decreased until P140. Congenic controls, however, showed no MHC class II-positive cells in the retina. Cells double-labeled with OX6 and ED1 were present in the outer nuclear layer at P42, but no OX6 or OX42 double-labeled cells were detected. Also, no ED2-positive cells were detected. Our results suggest that MHC class II-positive cells may play some role in retinal dystrophy.

[Prevention and control of nosocomial infection caused by methicillin resistant Staphylococcus aureus in premature infant ward--prevention effect of "povidone iodine solution" wipe of neonatal skin].

In January 1983, a number of premature infants under management in the premature infants' unit of our hospital were found to have bacteremia due to Staphylococcus aureus. By the end of February of the same year, 4 of these infants, who had been treated in the same unit, developed impetigo. The S. aureus responsible for this condition was classified as type IV by a coagulase typing. In a subsequent antimicrobial susceptibility test using the disk diffusion method, this microorganism was found to be resistant to methicillin, erythromycin and lincomycin, and to be susceptible to tetracycline, chloramphenicol and cefmetazole, indicating that it was a methicillin resistant S. aureus (MRSA). Because the result from the coagulase typing agreed with the antimicrobial susceptibility pattern in all cases, we concluded that these cases represented nosocomial infection with MRSA. The source and route of the infection were investigated, and measures taken to prevent bacterial spread from carriers and to keep instruments and environments clean. Although the source of infection was not identified. Then, we tried wiping the body surface of the premature infants with an Isodine solution (10% PVP-I, 1:100 dilution) in order to prevent colonization of the microorganism on the body surface. With this application+, MRSA was no longer detected from the body surface of the premature infants, and no additional MRSA infection occurred in the premature infants' unit. Data collected for premature infants' managed at our hospital in the subsequent 6 years allows us to conclude that MRSA infection can be almost completely controlled by frequent surveys of carriers and appropriate body surface wiping with Isodine solution.(ABSTRACT TRUNCATED AT 250 WORDS)