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Submicron scale hybrid structures of diluted magnetic semiconductor (DMS) quantum wells (QWs) with ferromagnetic Co wires have been developed for the purpose of applying microscopic magnetic fields to the DMS quantum structures. The Zn[sub 1-x-y]Cd[sub x]Mn[sub y]Se QW was made into wires with the width down to 0.1 μm and each wire was sandwiched between the Co wires. The magneto-optical properties of the hybrid structures were studied by spin–flip light scattering of paramagnetic Mn ions in the DMS QW in addition to ferromagnetic surface spin-wave scattering of the Co wires, where the spin–flip energy is highly sensitive to the magnetic field H[sub Co flux] applied from the Co wires. The application of uniform magnetic fields H[sub Co flux]>=0.25 T from the Co wires to the DMS QW has been attained with the Co-wire spacing of 0.2 μm. In addition, the distribution of H[sub Co flux] in the DMS QW is quantitatively evaluated from the spectral shape of the spin–flip scattering. Moreover, the application of H[sub Co flux] to the DMS QW is switched on and off by weak external fields less than 0.02 T depending on the magnetic shape anisotropy of the collective Co wires, which can realize the switching behavior of the spin alignment of magnetic ions in the DMS QW. © 2003 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Investigates the effect of light on the hardness of C60 crystals. Illumination with white light; Effectiveness in the temperature range of 298-380 K; Photopolymerized C60 molecules near the crystal surface; Explanation of the temperature dependence of the hardness.

Background: There is no well-established treatment strategy for Babesia gibsoni infection. A new therapeutic protocol using atovaquone (ATV) and azithromycin (AZM) has been proposed, but there is concern about the possible induction of relapse and the emergence of ATV-resistant variants after treatment. Objective: To evaluate the clinical use of combination therapy with ATV and AZM as a first-line treatment of clinical B. gibsoni infection in dogs, and to investigate the emergence of ATV-resistant variants. Animals: Eight B. gibsoni naturally infected dogs showing signs of acute onset of disease. Methods: Retrospective case study. Eight clinical cases received combination therapy with ATV and AZM at Kagoshima University Veterinary Teaching Hospital during 2007–2008, and their clinical courses and clinicopathological parameters were evaluated. In addition, alterations in the cytochrome b ( CYTb) gene of B. gibsoni were analyzed by polymerase chain reaction and DNA sequencing techniques. Results: All of the dogs responded well to the treatment, with rapid improvement in their clinical condition and hematological parameters. However, 5 of the 8 dogs relapsed after treatment. Analysis of the CYTb gene strongly suggested the emergence of ATV-resistant variants after treatment. Conclusions and Clinical Importance: The combination of ATV and AZM can be used as a first-line treatment for dogs with babesiosis, but relapses occur. Attention should be paid to the possible in vivo selection of drug-resistant variants. [ABSTRACT FROM AUTHOR]

The cellular damage over time and the alterations of neuronal subtypes was characterized in the striatum after 90-min middle cerebral artery occlusion and reperfusion in rats. We investigated the immunohistochemical alterations of choline acetyltransferase (ChAT)-positive (cholinergic-positive), γ-aminobutyric acid (GABA)ergic parvalbumin (PV)-positive, GABAergic nNOS (neuronal nitric oxide synthase)-positive interneurons, neuronal nuclei (NeuN)-positive spiny projection neurons, glial fibrillary acidic protein (GFAP)-positive strocytes and microglial response factor-1 (MRF-1)-positive microglia in the striatum after focal cerebral ischemia in rats. In the present study, transient focal cerebral ischemia in rats caused severe damage against interneurons as well as spiny projection neurons in the striatum. In contrast, a significant increase in the number of GFAP-immunopositive astrocytes was observed in the ipsilateral striatum 15 days after focal cerebral ischemia. Furthermore, a significant increase of MRF-1 immunoreactivity was observed in microglia of the ipsilateral striatum 7 days and 15 days after focal cerebral ischemia. Among three types of cholinergic interneurons, GABAergic PV-positive interneurons and GABAergic nNOS-positive interneurons, the severe damage of cholinergic and GABAergic PV-positive interneurons was more pronounced than that of GABAergic nNOS-positive interneurons after transient focal cerebral ischemia in rats. Furthermore, the present results suggest that GABAergic nNOS-positive interneurons in the striatum after focal cerebral ischemia undergo cellular death in a delayed manner. [ABSTRACT FROM AUTHOR]

The prevalence of hypovitaminosis D in patients with acute hip fracture was examined in a population on Sado Island in Japan. There were 85 cases of hip fracture among this population in 2004, giving an overall incidence of hip fracture of 121.4 per 100,000 population per year. This study included 50 of the 85 cases, and these cases were defined as the hip fracture group. Patients older than 70 years without established osteoporosis who were admitted to the hospital on the island during almost the same period for treatment of an orthopedic condition other than a hip fracture were defined as the control group. The levels of serum 25-hydroxyvitamin D (25-OHD), intact parathyroid hormone (intact PTH), alkaline phosphatase (ALP), albumin, and the number of remaining teeth were examined in each group. In the hip fracture group, serum calcium, serum phosphorus, urine N-terminal cross-linking telopeptide of type I collagen (NTx), bone mineral density (BMD) of the nonfractured hip, the presence of a vertebral fracture on X-ray, severity of dementia, and physical activity level were also examined. Both the serum 25-OHD and serum albumin levels were significantly lower in patients with hip fracture than in controls, and the intact PTH level was significantly higher in patients with hip fracture. The number of remaining teeth was correlated with age, and was also significantly correlated with 25-OHD. In the hip fracture group, 62% of the subjects had hypovitaminosis D (25-OHD <20 ng/ml) and one-fifth of cases with hypovitaminosis D showed elevated PTH levels (>65 pg/ml). On the other hand, in the control group, hypovitaminosis D occurred in 18.9% of the subjects, and only one case showed elevated PTH. The serum 25-OHD level showed a decrease as the severity of dementia progressed and the activity level decreased. Our results indicate that about two-thirds (62%) of hip fracture patients had vitamin D insufficiency, suggesting that this condition may be closely associated with hip fracture in elderly people. Therefore, the serum 25-OHD level may be a useful index for the risk of hip fracture in elderly people. [ABSTRACT FROM AUTHOR]

Abstract: We present a micro-photoluminescence (m-PL) study of electron-spin injection under magnetic fields in self-assembled semiconductor quantum dots (QDs) of CdSe. A characteristic band line-up of the CdSe QDs coupled with a diluted magnetic semiconductor quantum well (DMS-QW) of ZnCdMnSe through a ZnSe barrier layer enabled us to inject the electron spins from the DMS-QW into QDs. An experimental evidence of the electron-spin injection was provided by observations of circularly polarized m-PL spectra from individual QDs in this coupled QD structure. We find anti-correlation of PL intensity in between the DMS-QW (spin injector) and the individual QDs (spin receiver). [Copyright &y& Elsevier]

A hybrid nanostructure of diluted magnetic semiconductor quantum well (DMS-QW) has been fabricated by using a ferromagnetic Co/Pt-multilayered film with perpendicular magnetization. The nanoscale disk of DMS-QW with a diameter of 80 nm was embedded in the magnetic film generating magnetic fields perpendicular to the DMS-QW plane. As a result, exciton photoluminescence with circular-polarization properties arises in a zero external field, due to the giant Zeeman effects of excitons. It indicates that the perpendicular magnetic fields applied from the Co/Pt film align the exciton spins in the DMS nanoscale disk, acting as a nanoscale magnet for semiconductor spintronics. [ABSTRACT FROM AUTHOR]

Giant Zeeman effects of excitons in a hybrid nanostructure of diluted magnetic semiconductor (DMS) quantum well (QW) with ferromagnetic Co have been demonstrated, where the DMS-QW wire with the width of 200 nm is sandwiched in the Co wires and magnetic fields nearly perpendicular to the well plane can efficiently be applied from the Co wires to all of the DMS QW. The spectral shape of excitonic photoluminescence and the field dependence show clearly that the microscopic perpendicular fields generated from the Co wires induce the giant Zeeman shifts of excitons in the DMS QW. [ABSTRACT FROM AUTHOR]

Dynamic magnetic properties of epitaxial MnAs thin films are studied by means of Brillouin light scattering (BLS). The sharp spectral peaks of the inelastic BLS are observed in room temperature, which are attributed to surface spin waves indicating the long-wavelength collective behavior of ferromagnetic spins. The field dependence of the surface spin-wave frequency is strongly affected by an in-plane angle between the crystal axis and the external field direction in a GaAs(100)/MnAs(-1100) film, which originates from uniaxial magnetic anisotropy parallel to the MnAs[11-20] axis and the modified g value. Significant damping of the spin-wave BLS spectrum is observed with increasing excitation laser power, possibly due to thermal effects. © 2004 American Institute of Physics. [ABSTRACT FROM AUTHOR]

A response to a letter to the editor about an article dealing with hypovitaminosis D and secondary hyperparathyroidism in the elderly is presented.

A response to the article by Fisher and others published earlier is presented on Calcium-PTH-vitamin D axis in older patients with hip fracture.

Objective: Recent reports showed that low-dose aspirin was ineffective in the primary prevention of cardiovascular events in diabetic patients overall. We hypothesized that low-dose aspirin would be beneficial in patients receiving insulin therapy, as a high-risk group.Research Design and Methods: This study is a subanalysis of the Japanese Primary Prevention of Atherosclerosis With Aspirin for Diabetes (JPAD) trial-a randomized, controlled, open-label trial. We randomly assigned 2,539 patients with type 2 diabetes and no previous cardiovascular disease to the low-dose aspirin group (81 or 100 mg daily) or to the no-aspirin group. The median follow-up period was 4.4 years. We investigated the effect of low-dose aspirin on preventing atherosclerotic events in groups receiving different diabetes management.Results: At baseline, 326 patients were treated with insulin, 1,750 with oral hypoglycemic agents (OHAs), and 463 with diet alone. The insulin group had the longest history of diabetes, the worst glycemic control, and the highest prevalence of diabetic microangiopathies. The diet-alone group had the opposite characteristics. The incidence of atherosclerotic events was 26.6, 14.6, and 10.4 cases per 1,000 person-years in the insulin, OHA, and diet-alone groups, respectively. In the insulin and OHA groups, low-dose aspirin did not affect atherosclerotic events (insulin: hazard ratio [HR] 1.19 [95% CI 0.60-2.40]; OHA: HR 0.84 [0.57-1.24]). In the diet-alone group, low-dose aspirin significantly reduced atherosclerotic events, despite the lowest event rates (HR 0.21 [0.05-0.64]).Conclusions: Low-dose aspirin reduced atherosclerotic events predominantly in the diet-alone group and not in the insulin or OHA groups. [ABSTRACT FROM AUTHOR]

Telmisartan, an angiotensin II type 1 receptor blocker (ARB), acts as a partial agonist for peroxisome proliferator-activated receptor-γ, and thus improves abnormalities of glucose metabolism and hypertriglyceridaemia in addition to its documented blood pressure-lowering effects. Recently, it has been demonstrated that telmisartan also lowers the levels of total cholesterol and low-density lipoprotein (LDL) cholesterol levels. This study was designed to investigate the mechanism of cholesterol reduction. We measured serum levels of cholestanol, a cholesterol absorption marker, and lathosterol, a cholesterol synthesis marker, in 20 patients with both hypercholesterolaemia and hypertension. Ten patients were treated with telmisartan and the remaining 10 with fluvastatin. After 3 months of treatment, total and LDL cholesterol levels decreased in the telmisartan group ( P < 0·01 for both total and LDL cholesterol levels) and the fluvastatin group ( P < 0·001 for both total and LDL cholesterol levels). The change in cholestanol level after 3 months of treatment was positively correlated with the levels of total ( R = 0·72, P < 0·05) and LDL cholesterol ( R = 0·81, P < 0·01) in the telmisartan group. The change in lathosterol level was positively correlated with the levels of total ( R = 0·88, P = 0·001) and LDL cholesterol ( R = 0·89, P = 0·001) in the fluvastatin group. Our results suggest that the cholesterol-lowering effect of telmisartan might be caused by inhibition of cholesterol absorption, whereas that of statins is by inhibition of cholesterol synthesis. If confirmed, co-treatment with the two agents may be useful for synergistically lowering cholesterol in hypertensive patients. [ABSTRACT FROM AUTHOR]

Abstract: We study on the transfer dynamics of spin-polarized excitons into self-assembled quantum dots (QDs) of CdSe coupled with a diluted magnetic semiconductor (DMS) layer of ZnMnSe through a ZnSe barrier layer. A variation in the degree of circular polarization P of excitonic photoluminescence in the coupled QDs was observed between samples with different thicknesses (L B) of the non-magnetic barrier. Relatively high values of P (∼0.3) were obtained in the samples with L B=1 or 2nm, and the time dependences of the P value indicate the spin-transfer dynamics. From the L B dependence of the spin-transfer time, the spin-transfer mechanism is discussed, namely spin-conserving energy transfer. [Copyright &y& Elsevier]

Abstract: Micro-photoluminescence (PL) has been studied in magnetic fields for single quantum nanostructures, such as, a quantum wire (QWR) and dot (QD) of Zn1− x − y Cd x Mn y Se diluted magnetic semiconductor (DMS), where the DMS nanostructures were fabricated by means of electron-beam lithography. The giant Zeeman shift of excitons in the DMS-QWRs with the widths less than 50nm appears larger than that in a quantum well (QW), which can be attributed to suppression of the exciton diffusion into deeper local sites with less Mn-content. In addition, the DMS-QDs have successfully been fabricated. We show spin injection from the DMS to non-magnetic dots in a coupled QD structure. The spin injection is clearly shown by PL with the circular polarization degree up to 20% from the non-magnetic dot, which is higher than that of 11% in the case of coupled QW. Effects of exciton diffusion are also discussed in the dot structures. [Copyright &y& Elsevier]

Microwave spectra of six isotopic species of (E)- and (Z)-acetaldehyde oxime (CH3CD=NOH, CH3CH=15NOH, CH313CH=NOH, 13CH313CH=NOH, CD3CH=NOH, and CD3CD=NOH) were observed in the frequency range of 26.0–40. Adding to normal species and CH3CH=NOD, the rs coordinates of H1, N, C1, C2, and H3 atoms (refer to Fig. 1) of (E) and (Z) isomers in A-state were calculated using Kraitchman's equation. The structural parameters, three bond lengths and three bond angles of (E)- and (Z)-acetaldehyde oxime in A-state were determined. The structural parameters obtained are as follows: for E isomer, r(C1=N): 1.265(15) Å, r(C1–C2): 1.510(11) Å, r(C1–H1): 1.110(9) Å, ∠C2C1N: 117.7(8)°, ∠H1C1N: 118.1(5)°, and ∠C2C1H1: 124.2(7)°, and for Z isomer, r(C1=N): 1.275(4)Å, r(C1–C2): 1.510(14)Å, r(C1–H1): 1.091(8) Å, ∠C2C1N: 124.3(7)°, ∠H1C1N: 113.6(5)°, and ∠C2C1H1: 122.1(7)°. The bond angle ∠C2C1N in Z isomer is much larger than that of (E) isomer, because of the steric repulsion between the methyl and hydroxyl groups in (Z) isomer. The steric repulsion may be related to the low barrier height (V3) of the methyl group in Z isomer. [Copyright &y& Elsevier]

Presents a study which examined the production and regulation of extracellular superoxide dismutase and renal glomerular mesangial cells. Methods; Results; Discussion.

A reply to a letters to the editor about an article on difference in the birth order effect in the much younger generation that was published in a previous issue is presented.

The article describes the case of a 62-year-old woman with a giant submucosal tumor (SMT) in the descending colon. Topics discussed include the successful en bloc resection of a large submucosal lipoma of the colon by endoscopic submucosal dissection (ESD), the technical aspects of the ESD procedure, and the procedure used to make the giant SMT hang from the colonic wall.