Annulated dinuclear palladium(II) phthalocyanine complex as an effective photo-oxidation catalyst for near-infrared region light

An annulated dinuclear palladium(II) phthalocyanine complex (1) was synthesized and characterized. It was found that 1 worked as a photo-catalyst for the decomposition of 1,3-diphenylisobenzofuran (DPBF) in aerated toluene under the irradiation of the light in the near-infrared (NIR) region (λ > 780 nm).     

Assessment of the impact of cattle testing strategies on human exposure to BSE agents in Japan

In Japan, cattle screening tests for BSE are conducted at slaughterhouses for surveillance purposes and as a meat safety measure, but the public health impacts of such testing and the subsequent removal of positive animals from the food chain have not been quantitatively assessed. We evaluated the influence of removing specified risk materials and the alternation of age limits for testing cattle at the slaughterhouse on human exposure to the BSE agent in Japan by constructing a probabilistic risk model. A stochastic model using Monte Carlo simulation was constructed in order to estimate the BSE infectivity destined for the food chain from a single BSE-infected animal at slaughter. The impact of different testing strategies and risk material removal were then compared. Murine intra-cerebral ID50 (m.i.c. ID50) units were used as units for BSE infectivity. Sensitivity analysis was conducted for key input variables by changing values within plausible ranges. The expected fraction of BSE-infected cattle presented for slaughter that would be detected by screening tests was 20%, even if all slaughtered cattle were tested. The removal of risk materials reduced the median value estimate of infectivity destined for human consumption by 95%. Cattle screening tests reduced the infectivity further, but reduction efficacy did not differ among the various testing strategies. Sensitivity analysis indicated that the characteristics of BSE infectivity accumulation during the incubation period, extension of the incubation period, and lowering the detection limit of screening tests had no significant impact on relative infectivity reduction, which remained stable irrespective of testing strategy or changes in these parameters. This study suggests that the impact of changing the age limit for testing cattle on beef safety is small, provided that the removal of risk materials is conducted properly.     

Bone formation following implantation of fibrous calcium compounds (β−Ca(PO3)2, CaCO3(aragonite)) into bone marrow

Bone formation around three types of fibrous calcium-containing crystals has been examined histologically using rats. The implanted materials are (i) calcium metaphosphate (–Ca(PO₃)₂) fibers having aspect ratios of 15–80 with 2–20 m in diameter, (ii) –Ca(PO₃)₂) fibers surface-modified using dilute NaOH and (iii) calcium carbonate (CaCO₃; aragonite phase) whiskers having aspect ratios of 15–40 with 0.5–3 m in diameter. –Ca(PO₃)₂ fibers show a mechanically high strength with a low modulus of elasticity, and the surface-modified fibers have a thin layer consisting of a calcium orthophosphate phase. CaCO₃ whiskers were used for comparison reasons. The materials were implanted for 4, 8, and 12 weeks into bone defects created in the bone marrow of rat tibiae. Cancellous bone formation was observed around –Ca(PO₃)₂ fibers, the surface-modified fibers and CaCO₃ whiskers after implantation for 12, 4 and 4 weeks, respectively. CaCO₃ whiskers were scarcely observed after 12 weeks for resorbing. The calcium phosphate fibrous materials show combined advantages of mechanically high strength for toughening a matrix phase and biological activities; thus, these materials may prove to be useful for novel applications in the biomedical field.     

Porous Glass-Ceramics with Bacteriostatic Properties in Silver-Containing Titanium Phosphates: Control of Release of Silver Ions from Glass-Ceramics into Aqueous Solution

Porous glass-ceramics with the surface phase consisting predominantly of AgTi₂(PO₄)₃ crystal and the interior phase of LiTi₂(PO₄)₃ crystal are prepared by exchange of Ag⁺ions for Li⁺ions. In the present work, the release of Ag⁺ ions from glass-ceramics into aqueous solutions was investigated. Exchanged Ag⁺ ions were chemically stable in water. The as-exchanged glass-ceramics released Ag⁺ ions of 3045 equiv/g into phosphate buffer solution containing Na⁺ ions. X-ray diffraction analysis showed that silver-containing titanium phosphate crystalline phase in the glass-ceramics did not deteriorate even by heating at 900°C. The amount released from the heated glass-ceramics into the buffer solution was found to decrease drastically by 1–2 μequiv/g. The heated glass-ceramics showed excellent bacteriostatic properties. Glass-ceramics are expected to be novel bacteriostatic materials which have high thermal resistance and are medically safe.     

用RHEED方法分析半导体薄膜特性

在讨论ＲＨＥＥＤ原理的基础上，介绍了组建的ＲＨＥＥＤ和其附属的真空系统，并用此装置得到了Ｓｉ薄膜的ＲＨＥＥＤ衍射花样。本文还对实验条件和实验结果进行了简单的分析和介绍。     

Apatite Formation on Calcium Phosphate Invert Glasses in Simulated Body Fluid

Calcium phosphate invert glasses, which contain P₂O₇²⁻ and PO₄³⁻ ions, have been prepared via the addition of a small amount of TiO₂. The formation of bonelike calcium phosphate apatite on the surface of the phosphate invert glasses was examined in simulated body fluid (SBF) at a temperature of 37°C. Soaking for 20 d resulted in the deposition of leaflike apatite particles on 6CaO·3P₂O₅·TiO₂ invert glass (based on molar ratio). The glass had much-greater chemical durability against SBF, in comparison with a metaphosphate glass; P ions were not dissolved excessively from the 6CaO·3P₂O₅·TiO₂ glass, so the apatite formation was not suppressed.     

Prophylactic Therapy with Human Amniotic Fluid Stem Cells Improves Long-Term Cognitive Impairment in Rat Neonatal Sepsis Survivors

A systemic inflammatory response induces multiple organ dysfunction and results in poor long-term neurological outcomes in neonatal sepsis. However, there is no effective therapy for treating or preventing neonatal sepsis besides antibiotics and supportive care. Therefore, a novel strategy to improve neonatal sepsis-related morbidity and mortality is desirable. Recently, we reported that prophylactic therapy with human amniotic stem cells (hAFSCs) improved survival in a rat model of lipopolysaccharide (LPS)-induced neonatal sepsis through immunomodulation. Besides improving the mortality, increasing survival without major morbidities is an important goal of neonatal intensive care for neonatal sepsis. This study investigated long-term neurological outcomes in neonatal sepsis survivors treated with hAFSCs using the LPS-induced neonatal sepsis model in rats. We found that prophylactic therapy with hAFSCs improved spatial awareness and memory-based behavior in neonatal sepsis survivors at adolescence in rats. The treatment suppressed acute reactive gliosis and subsequently reduced astrogliosis in the hippocampal region over a long period of assessment. To the best of our knowledge, this is the first report that proves the concept that hAFSC treatment improves cognitive impairment in neonatal sepsis survivors. We demonstrate the efficacy of hAFSC therapy in improving the mortality and morbidity associated with neonatal sepsis.     

Hypertriglyceridemia in nephrotic rats is due to a clearance defect of plasma triglyceride: overproduction of triglyceride-rich lipoprotein is not an obligatory factor

This study was conducted to determine whether overproduction of triglyceride-rich lipoprotein is an obligatory factor for experimental hypertriglyceridemia in nephrotic rats. Nephrosis was induced in male Wistar rats by administration of 150 mg/kg puromycin aminonucleoside. Nephrotic rats had slightly increased triglyceride secretion rate (TGSR) estimated using Triton WR1339 (0.53 +/- 0.05 vs. 0.45 +/- 0.04 mg/min, P < 0.05 vs. control rats) and marked hypertriglyceridemia (330.4 +/- 78.6 mg/dl). Rats made diabetic by 40 mg/kg streptozotocin were normotriglyceridemic (66.3 +/- 12.1 mg/dl) but had suppressed TGSR (0.33 +/- 0.09 mg/min). Experimental nephrosis was induced in diabetic rats. Their TGSR remained suppressed (0.35 +/- 0.06 mg/min) but they had marked hypertriglyceridemia (296.6 +/- 72.4 mg/dl) suggesting further impairment of triglyceride removal from the circulation in diabetic rats caused by nephrosis. Endogenously radiolabeled very low density lipoprotein (VLDL)-triglyceride from donor rats was reinjected into normal recipient rats. [3H]VLDL from the experimental groups (the rats with nephrosis, diabetes with nephrosis, and diabetes alone) were more slowly cleared by normal rats than VLDL from normal rats. These results suggest that circulating insulin is essential for increased triglyceride secretion in experimental nephrosis and that nephrotic hypertriglyceridemia can be induced only by a triglyceride removal defect. Therefore, hypersecretion of triglyceride-rich lipoprotein is not an obligatory factor for nephrotic hypertriglyceridemia.     

Alpha-fetoprotein producing pulmonary blastoma in a patient with systemic sclerosis: pathogenetic analysis

We describe a rare case of pulmonary blastoma complicated with systemic sclerosis. The serum alpha-fetoprotein level was elevated at presentation and the biopsied tumour stained positively against anti-alpha-fetoprotein antibody. The alpha-fetoprotein produced autonomously by tumour cells was of yolk-sac origin. Although the pathogenesis of pulmonary blastoma has not been clarified, we suggest that this pulmonary blastoma is a type of yolk-sac tumour.     

Effects of pancreatic polypeptide family peptides on feeding and learning behavior in mice

We studied the effects of intra-third cerebroventricular administration of neuropeptide Y (NPY), peptide YY (PYY) and pancreatic polypeptide (PP) on the locomotor activity and the feeding and learning behavior of mice. NPY (0.3-10 micrograms), PYY (0.1-10 micrograms) and PP (3.0-10 micrograms) produced significant increases in locomotor activity. A significant decrease was then observed 15 min after administration of 10 micrograms of PYY. NPY, PYY and PP significantly increased food intake at 20 min and this effect continued for 2 to 4 hr at the high doses. The feeding response to PP family peptides were quite similar to that in locomotor activity with respect to dose-response, time course and peptide specificity. Learning behaviors were evaluated at three different stages of memory processing, acquisition, consolidation and retrieval, in a battery of step-down type passive avoidance tests. NPY and PYY had no effect on acquisition, but significantly improved consolidation at a dose of 0.03 and 0.3 microgram, respectively. NPY also improved retrieval at a dose of 0.03 microgram. The ranking order of potency in stimulating feeding and locomotor activity was PYY > NPY > PP, and in improving memory consolidation NPY > PYY > PP. These observations suggest that NPY and PYY influence different neural substrates in the brain involved in feeding and learning.