Erosion of accel grids of ion engine due to sputtering

The erosion rates of extraction electrodes of ion sources due to ion beam irradiation are largely affected by amount of projectiles retained in the electrodes. A Monte Carlo simulation code ACAT has been used to calculate sputtering yields and reflection coefficients by simulating the accumulation effect of projectiles in a target material. The results for Xe projectiles-C target combination have indicated that both sputtering yields and reflection coefficients are largely enhanced by Xe retention, particularly at larger incident angle for the surface normal with low incident energy.

Involvement of resistance to apoptosis in the pathogenesis of endometriosis

Endometriosis, a disease affecting 3-10% of women of reproductive age, is characterized by the ectopic growth of endometrial tissue. Increasingly, endometriosis is also becoming recognized as a condition in which ectopic endometrial cells exhibit abnormal proliferative and apoptotic regulation in response to appropriate stimuli. Apoptosis plays a critical role in maintaining tissue homeostasis and represents a normal function to eliminate excess or dysfunctional cells. Accumulated evidence suggests that, in healthy women, endometrial cells expelled during menstruation do not survive in ectopic locations because of programmed cell death, while decreased apoptosis may lead to the ectopic survival and implantation of these cells, resulting in the development of endometriosis. Both the inability of endometrial cells to transmit a 'death' signal and the ability of endometrial cells to avoid cell death have been associated with increased expression of anti-apoptotic factors and decreased expression of pre-apoptotic factors. This paper is a review of the recent literature focused on the differential expression of apoptosis-associated molecules in the normal endometria of women without endometriosis, and in the eutopic and ectopic endometria of women with endometriosis. The role of apoptosis in the pathogenesis of endometriosis and the basic and clinical research on the current medical treatment for endometriosis from the view of apoptosis will be discussed.

Behavioural and morphological differences between feral and domesticated strains of common carp Cyprinus carpio

Morphological and behavioural traits of a feral strain of the common carp Cyprinus carpio from Lake Biwa in Japan were compared with those of two domesticated strains reared in Japan (one commercial strain and one ornamental koi). To compare genetically inherited traits, all fish were reared from eggs under similar environmental conditions. Using these fish, the following five traits were compared among the three strains: body shape, consumption rate of two types of free-swimming shrimp, medaka Oryzias latipes and bottom-dwelling chironomid larvae prey items, preference for a bottom habitat, feeding skills in detecting prey and escape response to predator attack. The feral strain of fish had more streamlined bodies, higher consumption rates for free-swimming prey, a greater preference for a bottom habitat, possessed greater skill in detecting prey and were more cautious of predator attacks, compared with the fish of the two domesticated strains. These characteristics shown by the feral fish are probably adaptive to the natural environment. A genetic analysis based on five nuclear single nucleotide polymorphism markers, however, suggested that the feral strain was relatively recently derived from domesticated stocks. Considering this, the present results appear to indicate the possibility that domesticated C. carpio could re-adapt to the wild environment during a short evolutionary period, although further research using more feral strains is required.

Ezetimibe improves postprandial hyperlipidaemia in patients with type IIb hyperlipidaemia

BACKGROUND

Postprandial hyperlipidaemia is known to be a high-risk factor for atherosclerotic disease because of rapid and lasting accumulations of triglyceride-rich lipoproteins and remnants. The Niemann-Pick C1-Like 1 (NPC1L1) protein acts as an intestinal cholesterol transporter and ezetimibe, which inhibits NPC1L1, has been used in patients with hypercholesterolaemia. We investigated effects of ezetimibe on fasting lipid and lipoprotein profiles and postprandial hyperlipidaemia in patients with type IIb hyperlipidaemia.

MATERIALS AND METHODS

Ezetimibe 10 mg per day was administered in ten patients with type IIb hyperlipidaemia for 2 months, and lipid and lipoprotein profiles were examined during fasting and after an oral fat loading (OFL) test.

RESULTS

In the fasting state, ezetimibe significantly decreased not only total cholesterol, low density lipoprotein (LDL)-cholesterol and apolipoproteinB-100 (apoB-100) levels but triglycerides (TG), apoB-48 and remnant lipoprotein cholesterol (RemL-C) levels. High performance liquid chromatography analysis showed that ezetimibe decreased cholesterol and TG levels in the very low density lipoprotein (VLDL) and LDL size ranges as well as apoB-100 levels, suggesting a decrease in numbers of VLDL and LDL particles. After OFL, ezetimibe decreased the area under the curve for TG, apoB-48 and RemL-C. Ezetimibe decreased postprandial elevations of cholesterol and TG levels in the chylomicrons (CM) size range, suggesting that the postprandial production of CM particles was suppressed by ezetimibe.

CONCLUSIONS

These findings suggest that ezetimibe improves fasting lipoprotein profiles and postprandial hyperlipidaemia by suppressing intestinal CM production in patients with type IIb hyperlipidaemia and such treatment may prove to be effective in reducing atherosclerosis.

High maneuverability guidewire with functionally graded properties using new superelastic alloys

Nitinol shape memory alloys (SMAs) are attracting considerable attention as core materials for medical guidewires because of their excellent flexibility and shape retention. However, since Nitinol guidewires possess low rigidity, the pushability and torquability of the guidewires are insufficient. On the other hand, although guidewires made of stainless steel have high pushability, plastic deformation occurs easily. We have developed a new class of superelastic guidewires with functionally graded properties from the tip to the end by using new SMA core materials such as Cu-Al-Mn-based or Ni-free Ti-Mo-Sn SMAs. The tip portion of the guidewire shows excellent superelasticity (SE), while the body portion possesses high rigidity. These functionally graded characteristics can be realized by microstructural control. These guidewires with functionally graded properties show excellent pushability and torquability and are considerably easier to handle than conventional guidewires with Nitinol or stainless steel cores. Moreover, a metallic catheter using a Ni-free Ti-based SMA with high biocompatibility is introduced.

Analysis of T cell receptor Vbeta diversity in peripheral CD4 and CD8 T lymphocytes in patients with autoimmune thyroid diseases

Autoimmune thyroid diseases are characterized by intrathyroidal infiltration of CD4(+) and CD8(+) T lymphocytes reactive to self-thyroid antigens. Early studies analysing T cell receptor (TCR) Valpha gene usage have shown oligoclonal expansion of intrathyroidal T lymphocytes but not peripheral blood T cells. However, TCR Vbeta diversity of the isolated CD4(+) and CD8(+) T cell compartments in the peripheral blood has not been characterized fully in these patients. We performed complementarity-determining region 3 (CDR3) spectratyping as well as flow cytometric analysis for the TCR Vbeta repertoire in peripheral CD4(+) and CD8(+) T cells from 13 patients with Graves' disease and 17 patients with Hashimoto's thyroiditis. Polyclonal TCR Vbeta repertoire was demonstrated by flow cytometry in both diseases. In contrast, CDR3 spectratyping showed significantly higher skewing of TCR Vbeta in peripheral CD8(+) T cells but not CD4(+) T cells among patients with Hashimoto's thyroiditis compared with healthy adults. We found trends towards a more skewed CDR3 size distribution in those patients having disease longer than 5 years and requiring thyroid hormone replacement. Patients with Graves' disease exhibited no skewing both in CD4(+) and CD8(+) T cells. These findings indicate that clonal expansion of CD8(+) T cells in Hashimoto's thyroiditis can be detected in peripheral blood and may support the role of CD8(+) T cells in cell-mediated autoimmune attacks on the thyroid gland in Hashimoto's thyroiditis.

Isolation and characterization of 15 microsatellite loci for the Japanese gudgeon Sarcocheilichthys variegatus

A microsatellite-enriched genomic library was obtained for the Japanese gudgeon Sarcocheilichthys variegatus microoculus, and 15 dinucleotide markers were successfully isolated and characterized. These markers were also available for other Japanese congeners, Sarcocheilichthys variegatus variegatus and Sarcocheilichthys biwaensis. In three populations of Sarcocheilichthys from Lake Biwa and the Ashida River in western Japan, seven to 27 alleles were observed for each locus. Linkage equilibrium was observed among most loci, and only one locus showed significant deviation from Hardy-Weinberg equilibrium in a population. These microsatellite markers will be useful for studies of the genetic structure of the Japanese gudgeons.

A case of acute radiation syndrome from the dermatological aspect

Accidental whole-body overexposure of radiation occurs very rarely. Radiation exposure causes DNA breaks in the cells and shows various clinical features, which are time dependent, dose dependent and tissue dependent. Neutron rays are more destructive than gamma rays but their actual effect on humans have been under-reported. We observed the time-dependent and the dose-dependent dermatological changes in a patient who was severely irradiated by neutron and gamma rays, with the aim of clarifying the clinicopathological features of severely irradiated skin. The detection of DNA breaks in keratinocytes was performed by the terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end labelling technique. The degenerative changes of the skin and the re-epithelialization varied in a time dependent and dose dependent manner. DNA breaks were significantly higher in irradiated keratinocytes. Neutron rays caused depth-dependent degeneration of the skin. Evaluation of DNA breaks in the skin cells might be a clue to estimate local dosimetry.

Bowel obstruction due to endometriosis in the rectovaginal septum

It is very rare that endometriotic lesions in the rectovaginal septum cause ileus. We report a case of bowel obstruction due to endometriotic lesions in the rectovaginal septum in a 22-year-old woman whose barium enema presented with apple-core-like findings. Diagnostic and treatment modalities were discussed. Preoperative and postoperative gonadotropin-releasing hormone analog and aromatase inhibitor therapy promote relief of clinical symptoms, a reduction of tumor volume and a better approach to radical surgery.

Comparison and evaluation of leakage flux on various types of dental magnetic attachment

A dental magnetic attachment is a device to retain dental prostheses such as overdentures by magnetic attraction. As compared with mechanical attachments, the dental magnetic attachment has superior characteristics such as easy insertion, good esthetics and less lateral pressure to its abutment tooth. As a result, it has come to be used widely. There are various types of dental magnetic attachments. There are a cup type and a sandwich type in Japan, and several types of dental magnetic attachments in other countries. They are used for a long term in the mouth, it is necessary to clarify those leakage magnetic fields. Therefore, in this paper, we evaluate the leakage magnetic fields leaking out of sandwich type and open magnetic circuit type of dental magnetic attachment.

[Mitral valve replacement for hypertrophic obstructive cardiomyopathy with repeated heart failure; report of a case]

A 62-year-old woman with hypertrophic obstructive cardiomyopathy suffered from repeated heart failure. Preoperative echocardiogrphy demonstrated pressure gradient (PG) of 64 mmHg in left ventricular cavity, mitral regurgitation II, and tricuspid regurgitation II with an ejection fraction of 74%. Cardiac catheterizaition revealed cardiac index of 1.50 l/min/m2. She was recommended mitral valve replacement (MVR) because she was hospitalized several times for heart failure. She underwent MVR, tricuspid annuloplasty, and modified maze operation. Postoperative PG fell till 15 mmHg in echocardiogrphy. Postoperative cardiac catheterization revealed cardiac index of 2.00 l/min/m2. MVR contributed to decrease of PG in intraventricular cavity and increase of cardiac output. Postoperative cardiac status was classified as New York Heart Association (NYHA) class I-II.