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The optical pick-up for DVD with CD (Compact Disc) compatibility is discussed. The difference of the substrate thickness between DVD and CD causes the different spherical aberration and prevents the laser beam from being focused into a diffraction limit spot size with only one objective lens. Several methods of reducing this aberration and possessing the compatibility with CD are proposed. The twin lens type optical pick-up is one solution of overcoming this problem. It incorporates objective lenses for both DVD and CD. Each lens results in an optimum focused spot without the extra spherical aberration for each type of disc.

Introduction: The thoracoscopic approach is becoming the standard for intrathoracic neurogenic tumors, though certain technical issues still need to be resolved. The purpose of this study is to evaluate the feasibility of thoracoscopic surgery for intrathoracic neurogenic tumors.

The acylzirconocene chloride complex as an acyl group donor reacts with ω-unsaturated α,β-enones and -ynones under Pd-Me2Zn(Me2AlCl)-catalyzed conditions to give stereoselectively bicyclo[3.3.0] compounds through (i) formation of a Pd(II) intermediate by an oxidative addition of the Pd(0) catalyst to an enone function, (ii) cyclization of the Pd intermediate to an ω-unsaturated group, (iii) an acyl group transfer from zirconium to Pd metal, (iv) reductive elimination of the Pd metal, and (v) intramolecular cis-selective aldol reaction.

The transfer of antigen-specific cellular immunity in human bone marrow transplantation (BMT) was studied in 49 donor-recipient pairs, using a varicella-zoster-virus (VZV) specific lymphoproliferative response (LPR) assay. Posttransplant VZV-LPR could be serially measured in 31 long-term surviving recipients. VZV-specific T-cell immunity was detected in the early posttransplant period in 4 of 16 recipients who were, and whose donors were, immune to VZV before BMT, but two of those positive responses diminished in the first 100 days posttransplant. No positive response was detected in the immediate posttransplant period when either only the recipient or the donor was immune to VZV pretransplant. Herpes zoster or chickenpox developed in the recipients depending on a history of pretransplant VZV infection when the VZV-LPR became negative, and recovery from VZV infection was always followed by quick conversion of VZV-LPR. Long-lasting positive VZV-LPR was observed in the two recipients who experienced VZV infection in the immediate pretransplant period and received marrow graft from an immune donor. Our results indicate that a simple or direct transfer of VZV-specific cellular immunity from a marrow donor to a recipient cannot be expected in usual clinical bone marrow transplantation and that there might be a collaboration or recruitment of immune responses involving both donor and recipient that permits the VZV-LPR to remain positive posttransplant.

We report a Japanese Becker muscular dystrophy (BMD) patient with occasional myalgia and cramps during normal activity that developed at the age of 28 months. His family history was negative for neuromuscular diseases. Muscle biopsy analyses, including dystrophin immunostaining, disclosed no clinically relevant findings. The diagnosis of BMD was initially made at the age of 10 years, when indications of persistent high serum levels of CK prompted us to screen deletions in the dystrophin gene by amplification of 19 deletion-prone exons from the genomic DNA by the polymerase chain reaction (PCR). Among the exons examined, exons 13 and 17 were deleted. To clarify the size of the deletion, the dystrophin transcript was analyzed by reverse transcription PCR. The determined nucleotide sequence of the amplified product encompassing exons 10 to 20 disclosed that the entire segment corresponding to exons 13 to 18 (810 bp) was absent, a deletion that would be expected to cause the production of a dystrophin protein lacking 270 amino acids from the rod domain. This result indicates that occasional myalgia and cramps could be early clinical manifestations of mild BMD, especially in patients who have a deletion in the rod domain, and that deletion screening of the dystrophin gene might be the only reliable method to diagnose such cases.

For the boron films made by a d.c. glow discharge for a gas mixture of diborane and helium, numerous surface properties were intestigated and the characteristics of the boron film as a plasma facing material in fusion devices were evaluated. The ability of the boron film to getter the oxygen was estimated as about 1021O atoms m-2. The gettered oxygen in the boron film was observed in the surface to a depth of less than about 30 nm. The hydrogen concentration of the boron film made at room temperature was approximately 30%. The hydrogen in the film desorbed at about 573 K. This desorption temperature was considerably lower than that of graphite. These results directly indicate that the boron film coated on the graphite wall can largely reduce the particle recycling, in addition to the reduction in the oxygen impurity level in the plasma.

The authors report a 14-year-old boy with Wiskott–Aldrich syndrome complicated by progressive multifocal leukoencephalopathy after allogeneic bone marrow transplantation. Several therapeutic approaches were attempted, but there was no response. The patient died 2 months after the onset of neurologic symptoms. We detected three distinct, rearranged regions of JC virus in the cerebellum, occipital lobe, and brainstem. These findings suggest that the brain lesions had three independent origins.

Aim To examine the long term effect of bone marrow transplantation (BMT) on ovarian function in girls. Methods Eighteen girls who underwent BMT before menarche, had been disease free for more than six years, and were over 14 years of age at the time of study were investigated. The preparative regimen consisted of irradiation and chemotherapy. The occurrence of menarche and changes in basal serum follicle stimulating hormone (FSH) concentrations were studied. Results Twelve patients achieved menarche at a median age of 12.8 years. Age at transplant was significantly younger in patients who achieved menarche than in those who did not (mean (SD), 7.2 (0.5) v11.1 (1.7) years). Basal FSH began to rise to menopausal concentrations after 10 years of age, and the girls who did not experience menarche had a sustained rise in FSH concentrations. Among those with raised FSH concentrations, five girls experienced menarche while serum FSH values were decreasing and four achieved menarche while FSH remained raised. Conclusions The high incidence of menarche suggests a favourable outcome of ovarian function in girls who undergo BMT at a young age.

An upper limit on the cross section for the excitation of the Jp=1>+state at Ex=3.069 MeV in156Gd by inelastic proton scattering at Eo=25 MeV and ?LAB=35° is derived. This upper limit is compared with theoretical estimates. It is shown that the findings of the present experiment are consistent with the interpretation that nuclei are excited by the new M1 mode through the convection current part of the M1 operator.

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