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Notes: We have constructed a three-configurational surface magneto-optical Kerr effect system, which provides the simultaneous measurements of the "polar," "longitudinal," and "transverse" Kerr hysteresis loops at the position where deposition is carried out in an ultrahigh vacuum growth chamber. The present system enables in situ three-dimensional vectorial studies of ultrathin film magnetism with a submonolayer sensitivity. We present three-configurational hysteresis loops measured during the growth of Co films on Pd(111), glass, and Pd/glass substrates. © 2000 American Institute of Physics.

Notes: Ultraviolet (UV) irradiation is known to induce serious oxidative damage in the skin via lipid peroxidation. Nitric oxide (NO) synthesized by keratinocytes, melanocytes and endothelial cells in response to proinflammatory cytokines and UV radiation, has been reported to prevent UV-induced apoptosis in the skin. We have examined the effects of NO on UVB-induced lipid peroxidation in murine skin in vivo. UVB induced a dose-dependent increase in lipid peroxidation of skin extracts in vitro; however, lipid peroxidation in the skin in vivo remained unaffected at irradiation doses of less than 1·0 J cm−2 and decreased significantly at doses over 1·5 J cm−2 (P 〈 0·01). Time-delayed inhibition of lipid peroxidation in the skin in vivo was observed after irradiation at 1·5 J cm−2. Administration of N G-nitro- l-arginine methyl ester ( L-NAME), an inhibitor of NO synthesis, enhanced lipid peroxidation (P 〈 0·05), while it suppressed the ear-swelling response (ESR), a biological marker of inflammation. By contrast, administration of sodium nitroprusside, an NO enhancer, suppressed lipid peroxidation (P 〈 0·01), while it enhanced the ESR. Expression of inducible nitric oxide synthase (iNOS) was observed from 12 to 48 h postirradiation at doses of 0·4–1·6 J cm−2. The UVB-induced iNOS expression was markedly inhibited by L-NAME, suggesting that iNOS is a major enzyme in the production of NO. These results suggest that NO acts as a mediator of the inflammatory response in UVB-irradiated skin, and that lipid peroxidation is inversely regulated with the NO-mediated inflammatory response in vivo.

Notes: An electrically injected InGaN/GaN-based distributed Bragg reflector (DBR) laser was demonstrated. Surface grating was formed on both sides of ridge waveguide by chemically assisted ion beam etching technique. The observed threshold current was 375 mA with threshold voltage of 15.1 V for 500×3 μm2 devices. The emission of the DBR laser occurred in a single longitudinal mode at a wavelength of 401.3 nm. The ratio of sidemode suppression was found to be more than 13 dB until a current injection of 1 A. © 2000 American Institute of Physics.

Notes: The atomic force microscope (AFM) tip biased at around −15 V is found to be capable of locally modifying the entire thickness of 40-nm-thick semiconducting or superconducting YBa2Cu3O7−y microstrips in air. We show, using combined electrical and AFM measurements, that the local regions underneath the surface of the semiconducting or superconducting YBa2Cu3O7−y microstrips are transformed into either nonconducting or nonsuperconducting regions, respectively, upon applying the negatively biased AFM tip. The conductance of the nonsuperconducting regions is also found to be comparable to that of the superconducting regions before modification at 298 K. © 2000 American Institute of Physics.

Notes: Major non-cardiac surgery within 40 days of coronary angioplasty with stenting has high cardiac complication rates. We have performed a case-control study to determine whether the risk of vascular surgery might have increased in recent survivors of coronary artery bypass surgery (CABG). Using our vascular database from 1990 to 1999, we matched the cases who had vascular surgery within a month of CABG with controls by pre-operative comorbidities of diabetes mellitus, history of myocardial infarction (MI), history of congestive heart failure (CHF), and chronic renal insufficiency and compared the incidence of peri-operative MI, CHF, death, and other complications. Compared to case-matched controls, patients who underwent vascular surgery within a month of CABG suffered significantly greater mortality (20.6% vs. 3.9%, p 〈 0.005). The incidence of non-fatal cardiac complications was not significantly different between the groups. We conclude that the risk of mortality may be significantly greater in patients undergoing major vascular surgery within a month of CABG.

Notes: Dense fine-grained B4C was synthesized by the spark plasma sintering (SPS) method using mechanically activated elemental powders. Relative densities of up to 95% were achieved. When characterized by X-ray line broadening methods, the grains of the resulting product were determined to be nanometric in scale. However, transmission electron microscopy (TEM) observations showed the product to be composed of a mixture of fine (nanometric) crystallites and grains in the micrometer range. The TEM images showed a highly defective structure containing a high density of twins. Their presence is the reason for the discrepancy between the X-ray and TEM results.

Notes: Abstracts Aims/hypothesis. Infiltration of mononuclear cells and glomerular enlargement accompanied by glomerular cell proliferation are very early characteristics of the pathophysiology of diabetes. To clarify the mechanism of early diabetic nephropathy, we measured [3H]-thymidine incorporation and cell numbers to show the influence of a high ambient glucose concentration and the osmotic effect on rat mesangial cell proliferation. We also measured the effect of high glucose on the expression of intercellular adhesion molecule-1 and vascular adhesion molecule-1 by flow cytometry and semiquantitative RT-PCR in mesangial cells and the adhesion of leukocytes to mesangial cells. Methods/results. Cells exposed to high d-glucose (30 mmol/l) caused an increase in [3H]-thymidine incorporation and cell numbers at 24 and 48 h and normalized at 72 h (p 〈 0.05), whereas these changes were not found in high mannitol (30 mmol/l), IL-1β, or TNFα-stimulated mesangial cells. Cells exposed to high-glucose (15, 30, or 60 mmol/l) or osmotic agents (l-glucose, raffinose and mannitol) showed that intercellular adhesion molecule-1 expression began to increase after 24 h, reached its maximum at 24 and 48 h and gradually decreased afterwards. The stimulatory effects of high glucose and high mannitol on mRNA expression were observed as early as 6 h and reached its maximum at 12 h. Up-regulation of ICAM-1 protein and mRNA was also found in IL-1-β and TNF-α-stimulated mesangial cells. Neither vascular adhesion molecule-1 protein nor mRNA expression was, however, affected by high glucose and high mannitol. Notably, the protein kinase C inhibitors calphostin C and staurosporine reduced high glucose- or high mannitol-induced intercellular adhesion molecule-1 mRNA expression and high glucose-induced proliferation. Furthermore, the NF-ϰB inhibitor N-tosyl-l-phenylalanine chloromethyl ketone reduced high glucose- or high mannitol-induced intercellular adhesion molecule-1 mRNA expression and high glucose-induced proliferation. Results showed that high glucose (15, 30 mmol/l) or high concentrations of osmotic agents remarkably increased the number of adherent leukocytes to mesangial cells (p 〈 0.01) compared with control cells (5 mmol/l d-glucose). Functional blocking of intercellular adhesion molecule-1 on mesangial cells with rat intercellular adhesion molecule-1 monoclonal antibody, calphostin C, staurosporine, or N-tosyl-l-phenylalanine chloromethyl ketone significantly inhibited high glucose- or high mannitol-induced increase in leukocyte adhesion (p 〈 〈 0.05). Conclusion/interpretation. These results suggest that high glucose can upregulate intercellular adhesion molecule-1 protein and mRNA expression but not vascular adhesion molecule-1 expression in mesangial cells and promote leukocyte adhesion through up-regulation of intercellular adhesion molecule-1 through osmotic effect, possibly depending on the protein kinase C nuclear factor-kappa B (PKC-NF-ϰB) pathway. High glucose itself can also promote mesangial cell proliferation through the PKC-NF-ϰB pathways. We conclude that hyperglycaemia in itself seems to be an important factor in the development of early diabetic nephropathy. [Diabetologia (2000) 43: 1544–1553]

Notes: Abstract  Changes in bone turnover with years since menopause (YSM) are responsible for bone loss and play a major role in osteoporosis. Although single measurements of the bone turnover marker appear unlikely to be clinically useful in predicting bone mineral density, the usefulness of these measurements in relation to the YSM has not been well established. The establishment of this relationship was the aim of this study. To address this issue, we have measured a battery of sensitive and specific markers of bone turnover in 272 women postmenopausal from –5 to 15 a, and the data was correlated with bone mineral density (BMD) at different skeletal sites measured utilizing dual-energy X-ray absorptiometry (DXA). Bone formation was assessed by serum osteocalcin (OC), and bone resorption by Pyr and D-pyr. The three markers and BMD were compared between the groups (YSM). Among the three markers, only Pyr exhibited a significant difference between pre and postmenopausal groups. In the aspect of correlation between bone turnover marker and BMD according to the groups (YSM), we found negative strong correlations between the BMD of lumbar spine (L2–4) vs. Pyr (P=0.01, r=–0.75) in the premenopausal group (–5∼0 YSM), and we found negative correlation between the BMD of L2–4 vs. osteocalcin (P=0.05, r=–0.2 and P=0.01, r=–0.44) in the postmenopause groups (0∼5 and 5∼10 YSM). We concluded that Pyr in women –5∼0 YSM and osteocalcin in women 0∼10 YSM displayed negative correlation with BMD of L2–4.