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It has been reported that anti-A and anti-B (ABO antibody) titers decrease with age, but little is known about the association between ABO antibody titers and physiologic/biochemical parameters such as body mass index (BMI), gamma-glutamyl transpeptidase (GGT), and total cholesterol (T-Cho). We investigated the present situation of ABO antibody titers among healthy blood donors in Japan and the physiologic/biochemical factors that may be associated with changes in ABO antibody titers. Plasma from 7450 Japanese blood donors was tested for ABO antibody titers using ABO reverse typing reagents by an automated microplate system; donor samples were classified into low, middle, and high titers according to the agglutination results obtained with diluted plasma samples. Multivariate regression analysis was performed to analyze the association between ABO antibody titers and age, gender, biochemical parameters (alanine transaminase [ALT], GGT, globulin, T-Cho, and glycosylated albumin [GA]), and BMI according to the ABO blood groups. A significant correlation between ABO antibody titers and age/gender, except for gender in anti-A of blood group B donors, was observed. BMI showed significant but negative correlations with anti-A and anti-B (β = −0.085 and −0.062, respectively; p< 0.01) in blood group O donors. In addition, significant but negative correlations between GGT and T-Cho with anti-B of blood group A donors (β = −0.055 and −0.047, respectively; p< 0.05) were observed. Although differences existed among the ABO blood groups, ABO antibody titers seem to be associated with physiologic and biochemical parameters of healthy individuals.

Ann Rheum Dis 2002;61:617-622 Objective: To test the hypothesis that dynamic load at baseline can predict radiographic disease progression in patients with medial compartment knee osteoarthritis (OA). Methods: During 1991-93 [...]

In this paper, a system for supporting a knit designing is described. This system generates stitch symbols from a knitting pattern image. There are 24 kinds of stitch symbols. Each of them represents a basic simple pattern of a knitting. To implement this system on the computer, a method for recognizing string structure from a knitting pattern image and a method for representing string structures of the knitting pattern uniquely, are proposed. The utility of this system is verified from some execution examples.

Preparation of activated carbon from biomass residue with conventional steam activation was conducted to find the alternative raw materials for meeting the high demand for low-cost porous material in the desiccant application. In this study, activated carbons were produced from dead camphor leaves using two-step methods at different preparation temperatures. The characterization results revealed that the prepared activated carbons have a surface area of 700 m2/g, with 75% of microporosity. The water vapor sorption study reported that the water uptake of camphor leaf-based activated carbons was strongly affected by the pore properties of the materials. Moreover, from the water adsorption kinetics, it was observed that the rate constant of adsorption was varied at each relative pressure, which can be assumed that the water adsorption mechanism is different at each relative pressure. From these results, it was revealed that the prepared camphor leaf-based activated carbons have a promising ability to adsorb water vapor from humid air.

Nuclear magic numbers correspond to fully occupied energy shells of protons or neutrons inside atomic nuclei. Doubly magic nuclei, with magic numbers for both protons and neutrons, are spherical and extremely rare across the nuclear landscape. Although the sequence of magic numbers is well established for stable nuclei, experimental evidence has revealed modifications for nuclei with a large asymmetry between proton and neutron numbers. Here we provide a spectroscopic study of the doubly magic nucleus 78Ni, which contains fourteen neutrons more than the heaviest stable nickel isotope. We provide direct evidence of its doubly magic nature, which is also predicted by ab initio calculations based on chiral effective-field theory interactions and the quasi-particle random-phase approximation. Our results also indicate the breakdown of the neutron magic number 50 and proton magic number 28 beyond this stronghold, caused by a competing deformed structure. State-of-the-art phenomenological shell-model calculations reproduce this shape coexistence, predicting a rapid transition from spherical to deformed ground states, with 78Ni as the turning point. A spectroscopic study of 78Ni confirms its doubly magic nature and reveals it as a stronghold beyond which the magic numbers 28 and 50 break down because of competing deformation.

It has recently been recognised that adipose tissue, which accounts for more than 10% of body weight, is not only a reservoir for energy storage, but is also an endocrine [...]

We have studied thermal expansion of free standing polystyrene thin films using X-ray reflectivity to elucidate the glass transition temperature and the thermal expansivity. We found that the glass transition temperature Tgdecreased with the film thickness, depending on molecular weight. The reduction in the free standing films is much larger than in the supported films on Si substrate, suggesting that some segmental motions are activated due to free surfaces on both sides in the free standing films. We also found that the thermal expansivity in the glass and the melt decreased with the film thickness. This decrease must be attributable to chain confinement effects.

A remarkable change of the temperature dependence of complex permeabilities µ' and µ" is observed in single of crystals of yttrium iron garnet with an intense visible light at 77 K. Conspicuous double peaks of photoinduced disaccommodation (DA) around 130 K (DA(I)) and 200 K (DA(II)), with correlative onset of the irreversible decrease of µ' at low temperature were found. Estimated activation energies of these peaks are 0.46 eV for DA(I) and 0.7 eV for DA(II). In addition, we observed the third peak(DA(III), 0.88 eV) independent of irradiation around the room temperature. The estimated height of potential barrier around oxygen vacancy is 03 eV. A simple model for the explaining these results is presented here.

Nanoscale characterisation of a rolling–sliding wear surface layer of pearlitic steel was performed with transmission electron microscopy and atom probe tomography to reveal microstructural changes in the pearlite structure. Plastically deformed fine pearlitic lamellae with interlamellar spacing of ~10 nm were observed just beneath the contact surface after the rolling–sliding wear test, where the hardness of the surface reached >800 HV, twice the initial bulk hardness of 400 HV. Lamellar cementite was slightly decomposed, but most lamellar cementite was retained as thinned lamellae in the deformed pearlitic structure. The large increment in hardness was mostly explained by the reduction in interlamellar spacing. The formation mechanism of the microstructure of the worn surface was compared with that of the white etching layer on the pearlitic rail surface.

Summary. Background:Integrin αIIbβ3 plays key roles in platelet aggregation and subsequent thrombus formation. Hydrogen peroxide‐inducible clone‐5 (Hic‐5), a member of the paxillin family, serves as a focal adhesion adaptor protein associated with αIIbβ3 at its cytoplasmic strand.

Abstract: We present a first overview of the synplutonic mafic dykes (mafic injections) from the 2.56–2.52 Ga calcalkaline to potassic plutons in the Eastern Dharwar Craton (EDC). The host plutons comprise voluminous intrusive facies (dark grey clinopyroxene-amphibole rich monzodiorite and quartz monzonite, pinkish grey porphyritic monzogranite and grey granodiorite) located in the central part of individual pluton, whilst subordinate anatectic facies (light grey and pink granite) confined to the periphery. The enclaves found in the plutons include highly angular screens of xenoliths of the basement, rounded to pillowed mafic magmatic enclaves (MME) and most spectacular synplutonic mafic dykes. The similar textures of MME and adjoining synplutonic mafic dykes together with their spatial association and occasional transition of MME to dismembered synplutonic mafic dykes imply a genetic link between them. The synplutonic dykes occur in varying dimension ranging from a few centimeter width upto 200 meters width and are generally dismembered or disrupted and rarely continuous. Necking of dyke along its length and back veining of more leucocratic variant of the host is common feature. They show lobate as well as sharp contacts with chilled margins suggesting their injection during different stages of crystallization of host plutons in magma chamber. Local interaction, mixing and mingling processes are documented in all the studied crustal corridors in the EDC. The observed mixing, mingling, partial hybridization, MME and emplacement of synplutonic mafic dykes can be explained by four stage processes: (1) Mafic magma injected during very early stage of crystallization of host felsic magma, mixing of mafic and felsic host magma results in hybridization with occasional MME; (2) Mafic magma introduced slightly later, the viscosities of two magmas may be different and permit only mingling where by each component retain their identity; (3) When mafic magma injected into crystallizing granitic host magma with significant crystal content, the mafic magma is channeled into early fractures and form dismembered synplutonic mafic dykes and (4) Mafic injections enter into largely crystallized (>80% crystals) granitic host results in continuous dykes with sharp contacts. The origin of mafic magmas may be related to development of fractures to mantle depth during crystallization of host magmas which results in the decompression melting of mantle source. The resultant hot mafic melts with low viscosity rise rapidly into the crystallizing host magma chamber where they interact depending upon the crystallinity and viscosity of the host. These hot mafic injections locally cause reversal of crystallization of the felsic host and induce melting and resultant melts in turn penetrate the crystallizing mafic body as back veining. Field chronology indicates injection of mafic magmas is synchronous with emplacement of anatectic melts and slightly predates the 2.5 Ga metamorphic event which affected the whole Archaean crust. The injection of mafic magmas into the crystallizing host plutons forms the terminal Archaean magmatic event and spatially associated with reworking and cratonization of Archaean crust in the EDC.

Angiosarcoma is a rare, highly malignant tumor with a poor clinical outcome. From January 2004 to September 2005, we advocated transarterial chemotherapy using a port system for four patients with angiosarcomas of the face and scalp. A heparin coated ANTHRON P-U catheter was introduced into the feeding artery. The proximal part of the P-U catheter was connected to the port system and buried in subcutaneous tissue. The amount of chemotherapeutic drug applied using the port system was almost the same as the conventional intravenous dose. Paclitaxel was the standard agent, at 50–100mg/diluted in 15–30 ml of physiological saline fluid slowly injected over 0.5–1 hour. For immunotherapy where appropriate, r-IL2 was mainly used at a dose of 70.000U/diluted in 5ml of physiological saline fluid injected into the port system over 30 seconds. This was continued for two to three weeks (five days/week) until recognition of a disappearance of the tumor. Macroscopic size reduction of the tumor was achieved in three out of the four cases. One case could not be evaluated because of eruptions induced by immunotherapy. Unfortunately two patients died after placement of port system, but the other two are still alive and are enjoying useful lives. Transarterial infusion chemotherapy using such a port system may be particularly effective for angiosarcoma in the early stages because small lesions with limited invasion mean a small territory of blood supply to be covered, and useful life was possible because the port system embedded in subcutaneous tissue allows treatment in an out-patient clinic.

As endovascular surgery (EVS) of symptomatic unruptured aneurysms can result in symptom exacerbation due to intra-aneurysmal thrombosis or lump formation by coils, this treatment remains controversial.We present five women ranging in age from 58 to 76 years (mean 65.6 years) who suffered post-EVS symptom exacerbation attributable to local inflammation.The aneurysms measured from 8 to 25 mm (mean 19 mm) and were located at the cavernous portion in four patients and at the origin of the ophthalmic artery in one. All underwent endosaccular embolization under local anesthesia. Immediately after embolization, 24 h anticoagulation therapy was started via the continuous injection of heparin; they also received anti-platelet therapy.At one to three days post-EVS, all five patients manifested worsening of their cranial nerve symptoms.In three other patients the symptoms were improved after EVS. We posit that inflammation induced by coil embolization may worsen cranial nerve symptoms transiently.Our findings suggest that post-EVS follow-up is necessary and that patients exhibiting an inflammatory reaction be treated with anti-inflammatory drugs.

Radiation-induced radical polyaddition of bis(α-trifluoromethyl-β,β-difluorovinyl) terephthalate [CF2&dbd;C(CF3)OCOC6H4COOC(CF3)&dbd;CF2] (BFP) in the presence of an excess of cyclic and acyclic ethers in feed was examined at 0 °C using γ-ray irradiation. Irradiation of BFP with an 8-fold excess of 1,4-dioxane (DOX) and diethyl ether (EE) gave monomodal polymers consisting of the alternating unit of BFP and DOX moieties (poly(BFP-alt-DOX), &Mmacr;n,as-prepared = 5.1 × 10³) and of BFP and EE (poly(BFP-alt-EE), &Mmacr;n,as-prepared = 3.9 × 10³), respectively. The irradiation of BFP with an 8-fold excess of tetrahydrofuran or tetrahydropyran provided only 1:2 addition products in high yields. Monofunctional 2-benzoxypentafluoropropene [CF2&dbd;C(CF3)OCOC6H5] (BPFP) as a model compound showed preferential formation of the 2:1 adduct to the 1:1 adduct with DOX and EE. The kinetic analysis of the model reactions revealed that the rate constants for the formation of the 2:1 adducts (kd) of BPFP with DOX and EE were 2 orders of magnitude higher than those of the 1:1 adducts (km). Poly(BFP-alt-DOX) showed higher radiation resistance than poly(BFP-alt-EE) in solid state as well as in solution. It was concluded that radiation-induced step-growth polymerization under the stoichiometric imbalance of the two compounds requires a high kd/km value as well as high radiation resistance for the formation of high molecular weight polymers.

An experimental study of the pVTx properties for binary mixtures of HFC-32 (CH2F2) and HFC-125 (C2HF5) was conducted in the range of temperatures from 258 to 354 K, pressures up to 16.9 MPa, densities from 900 to 1400 kg·m−3, and compositions from 0 to 1 mole fraction of HFC-32, within the uncertainties of 4.8 mK of temperatures, 1.8 kPa of pressures, 0.022% of densities, and 0.0022 mole fraction of compositions. The present results were determined with the use of a constant-volume apparatus consisting of a cylindrical vessel of approximately 173 cm3 internal volume. The available data including the present measurements are critically compared with the equation of state developed by Tillner-Roth et al., and it is found that, in the liquid region for the range of compositions from 0.1 to 0.4 mole fraction of HFC-32, this equation of state is less reliable because of the lack of experimental data.

Abstract Bone cement consisting of polymethylmethacrylate (PMMA) powder and methylmethacrylate (MMA) liquid is clinically used for fixation of implants such as artificial hip joints. However, it does not show bone-bonding ability, i.e., bioactivity. The lack of bioactivity would be one of factors which cause loosening between the cement and the implant. The present authors recently showed the potential of bioactive PMMA-based bone cement through modification with ? -methacryloxypropyltrimethoxysilane (MPS) and calcium acetate. In this study, the effects of the kinds of PMMA powder on setting time, apatite formation and compressive strength were investigated in a simulated body fluid (Kokubo solution). The cement modified with calcium acetate calcined at 220 °C could set within 15 min when the PMMA powder had an average molecular weight of 100,000 or less. The addition of calcium acetate calcined at 120 °C in the PMMA powder required a much longer period for setting. The modified cements formed an apatite layer after soaking in the Kokubo solution within 1 day for cement starting from PMMA powder with a molecular weight of 100,000 or less. Compressive strengths of the modified cements were more than 70 MPa for cements starting from 100,000 and 56,000 in molecular weight. After soaking in Kokubo solution for 7 days, the modified cement consisting of PMMA powder of 100,000 in molecular weight showed a smaller decrease in compressive strength than that consisting of 56,000 in molecular weight. These results indicate that bioactive PMMA cement can be produced with appropriate setting time and mechanical strength when PMMA powders with a suitable molecular weight are used. Such a type of design of bioactive PMMA bone cement leads to a novel development of bioactive material for bone substitutes.

Abstract An experimental study of the pressure-volume-temperature-composition pVTx properties for binary mixtures of HFC- 32(CH2F2) and HFC-125(C2HF5) was conducted in the range of temperatures from 343 to 423 K, pressures from 4.0 to 15.6 MPa, densities from 485 to 491 kg·m-3, and compositions from 0.05 to 0.90 mole fraction of HFC-32, with uncertainties of 4.4 mK, 1.6 kPa, 0.02% , and 0.0004 mole fraction, respectively. The available experimental data for pVTx properties of binary mixtures of HFC-32 and HFC-125 have been compared with the equation of state developed by Tillner-Roth et al. From the critical evaluation, this equation of state should be revised in the range of low mole fractions of HFC-32.

Abstract Bonelike®/PLGA hybrid materials have been developed using ?-MPS as silane-coupling agent between the inorganic and organic phases for controlled drug delivery applications.

Summary. The aim of this study was to determine the effective and optimum dose of taurine for exercise performance and to maintain tissue taurine concentration. Rats received a respective daily dose of 0, 20, 100, and 500 mg/kg body weight of taurine (EC and ET-1, -2, -3 groups, respectively) for two weeks, and then, were subjected to treadmill until exhaustion. The running time to exhaustion was significantly prolonged by 25% and 50% in the ET-2 and -3 groups, respectively, compared to that in the EC group accompanied with maintenance of taurine tissue concentrations. Furthermore, the oxidative glutathione per total glutathione ratio in tissues was inhibited in the ET-2 and -3 groups whereas it was higher in the EC group than in both the no exercise and taurine-administered groups. Therefore the effective and optimal doses of oral taurine administration for two weeks on a transient exercise performance were between 100 and 500 mg/kg/day.

In the southern part of the Indian Peninsula, there are a number of alkaline plutons of Proterozoic age. In the northern part of the South Indian granulite terrain, the Yelagiri (syenite, pyroxenite) and Sevattur (syenite, pyroxenite, carbonatite) plutons intrude Archaean epidote-hornblende gneisses. Geochemical and isotopic characteristics of the Yelagiri and Sevattur plutons indicate that the syenitic magmas formed from highly differentiated mantle-derived alkali basalts. The Yelagiri and Sevattur syenites are characterized by evolved Sr and Nd isotopic compositions, pronounced enrichment in LILE and large negative Nb anomalies. Trace element and Sr-Nd isotope characteristics of the Yelagiri and Sevattur syenites are similar to those of the subduction-related alkaline rocks. The scarcity of geological evidence for subduction activity at the time of syenite intrusion during Neoproterozoic does not support a link between the alkaline magmatism and subduction. However, our data are consistent with the model of derivation of the Yelagiri and Sevattur syenites from the subcontinental lithospheric mantle, which was previously enriched by slab derived component. The geochemical and isotopic signatures of other mantle-derived intrusive rocks in the northern part of the South Indian granulite terrain with ages ranging from ca. 2.5 Ga to 0.75 Ga also support the above idea.

Eruptive and caldera-forming activity at Miyakejima volcano island, Japan, commenced on 26 June 2000 was accompanied by more than 40 day of seismic swarms and significant crustal deformation in the nearby islands and sea region besides those at Miyakejima itself. The migration of the hypocenters in the early stage suggests that they were triggered by magma intrusion from Miyakejima. However, it remains uncertain whether the long-lasting seismic swarms and ground displacements in the northern Izu-islands were totally maintained by the magma flow from Miyakejima, because another magma source nearby Kozushima was suggested previously, which is 40 km north-west of Miyakejima, based upon anomalous ground displacements. Here we report the detection of associated changes with the 2000 activity in both absolute gravity and elevation at Kozushima as well as those at Miyakejima. Combining these data with horizontal GPS displacements, we extend the analysis of Nishimura et al.(2001) and construct an optimum source model, so that we can account for the observed changes in geodetic data and determine the mass budget of the magma flow. The total mass of the newly intruded dike offshore of Miyakejima and nearby Kozushima turned out to be 130% or greater than the lost mass at Miyakejima. As long as there are no other source elements, another magma reservoir near Kozushima is required and is suggested to have been activated, causing the seismic swarms and crustal deformation. We may speculate as a phenomenology that the rapid lateral magma flow from Miyakejima in the very beginning of the unrest awakened a dormant reservoir offshore of Miyakejima and Kozushima.

Tunnel magnetoresistance (TMR) ratio as a function of annealing temperature for ferromagnetic tunnel junctions prepared using different oxidation methods was measured. The junction with plasma oxidation showed a TMR ratio of 31&percent; before heat treatment and it increased to 49&percent; after annealing at 300°C. On the other hand, the TMR ratio for the junction with radical oxidation showed a maximum at 350°C. The difference of thermal stability originates from the different oxidation procedure. The initial oxidation process of thin aluminium films was investigated by scanning tunnelling microscopy (STM). The STM images revealed progression of oxygen penetration into an aluminium film composed of small grains. Oxygen first covered the aluminium grain surface homogeneously for the plasma-oxidized junction; then oxygen inserted into the aluminium grain boundaries selectively for the radical-oxidized junction.

Rb-Sr and Sm-Nd isotopic studies were carried out for metamorphic rocks in the Namaqualand Metamorphic Complex, South Africa. The metamorphic rocks give the Rb-Sr mineral isochron ages (whole-rock - biotite - felsic fractions) of 844±85 Ma and 811.6±6.6 Ma for the lower granulite zone and of 776.5±5.4 Ma for the upper granulite zone. The rocks yield the Sm-Nd mineral isochron ages of 1071±18 Ma (whole-rock - garnet - felsic fractions) and 1067±158 Ma (whole-rock - hornblende - biotite rich fraction - felsic fractions) for the lower granulite zone and of 1052.0±3.6 Ma and 1002.5±1.4 Ma (whole-rock - garnet - felsic fractions) for the upper granulite zone. These age data suggest that the granulite facies metamorphism took place at 1060-1000 Ma, and that the rocks cooled down at 850-780 Ma. The Sr and Nd isotopic compositions of metamorphic rocks are different between the lower and upper granulite zones.

One of the current understandings of sulfur (S) doping of diamond is described, mainly from a theoretical point of view. First, some published experimental results are introduced. Then, two fundamental problems are defined: 1. whether an isolated substitutional S donor (Ssub) in diamond is shallower than a phosphorus (P) counterpart (Psub), and 2. whether an Ssub has a lower formation energy than a Psub. Recent theoretical (one quantum chemical, and two density-functional (DFT)) studies are reviewed to point out that theoretical results regarding the problems above have not converged yet. Results of the author's DFT calculations are presented for Ssub, and complexes of Ssub with hydrogen (H) as well as other elements such as nitrogen (N), and boron (B), and/or a vacancy. Formation energies of these defects are also presented.

Tantalum metal is a candidate for use as an implant material in high load-bearing bony defects, due to its attractive features such as high fracture toughness and high workability. This metal, however, does not have bone-bonding ability, i.e. bioactivity, and therefore the development of bioactive tantalum metal is highly desirable. It is known that the essential prerequisite for an artificial material to show bioactivity is to form a bonelike apatite layer on its surface in the body environment. The same type of apatite layer is formed in a simulated body fluid (SBF) with inorganic ion concentrations nearly equal to those of human blood plasma. The present authors previously showed that the apatite formation on tantalum metal in SBF was remarkably accelerated by treatment with 0.5 M-NaOH aqueous solution and subsequent firing at 300 °C, while untreated tantalum metal spontaneously formed the same apatite after a long soaking period. In the present study, the bonding strength of the apatite layer to the substrate was quantitatively evaluated in comparison with that to the untreated tantalum metal. Adhesive strength was measured as an estimation of bonding strength, and the surface microstructure of both the substrates was characterized in order to discuss the difference in the bonding strength in terms of surface structure. The apatite layer formed on the NaOH- and heat-treated tantalum metal shows higher adhesive strength than that formed on the untreated metal. The amorphous sodium tantalate layer formed on the tantalum metal by NaOH and heat treatments, has a smooth graded structure where its concentration gradually changes from the surface into the interior metal. Smooth graded structure with complex of apatite is constructed after soaking in SBF. The higher bonding strength of the apatite layer formed on the treated metal is attributed to its smooth graded structure.

We report an attempt to extract the pore structure of activated carbon from transmission electron microscopy (TEM) images. We have tried to use TEM of coconut-shell-based activated carbons, combined with image analysis, in order to make TEM a quantitative technique. It is important that the pore boundaries are clarified to analyze the pore structure, but extraction of the edges of pores is difficult by conventional techniques. In this work, we attempted to extract of the pore boundaries of the activated carbons by using fuzzy template obtained from a notion of a fuzzy topology.

Poly (methyl methacylate) (PMMA) bone cement is one of the popular bone-repairing materials for fixation of artificial hip joints. Significant problems on the PMMA bone cement are caused by loosening at the interface between bone and the cement, since the cement does not show bone-bonding, i.e. bioactivity. Development of PMMA bone cement capable of bone-bonding has been therefore long desired. The prerequisite for an artificial material to show bone-bonding is the formation of a biologically active bone-like apatite layer on its surface when implanted in the body. The same type of apatite formation can be observed on bioactive materials even in a simulated body fluid (Kokubo solution) with ion concentrations nearly equal to those of human blood plasma. Fundamental researches for bioactive glasses and glass-ceramics revealed that the apatite deposition is initiated by release of Ca2+ions from the material into the body fluid, and by catalytic effect of Si–OH groups formed on the surface of the material. These findings lead an idea that novel bioactive cement can be designed by incorporation of Si–OH groups and Ca2+ion into PMMA bone cement. In the present study, PMMA bone cement is modified with 20 mass % of various kinds of alkoxysilanes and calcium salts, and its apatite-forming ability was evaluated in Kokubo solution. The apatite formation was observed on the surface of the modified cements containing 20 mass % of CaCl2, irrespective of the kind of the examined alkoxysilane. On the other hand, the apatite formation was observed on the cement containing CaCl2, Ca(CH3COO)2or Ca(OH)2, but not on the cement containing CaCO3or β-Ca3(PO4)2, even when the cement contains 3-methacryloxypropyltrimethoxysilane (MPS). The results indicate that modification with alkoxysilane and calcium salts showing high water-solubility is effective for providing PMMA bone cement with bioactivity. © 2001 Kluwer Academic Publishers

The prerequisite for an artificial material to bond to living bone is the formation of bonelike apatite on its surface in the body. This apatite can be reproduced on its surface even in an acellular simulated body fluid with ion concentrations nearly equal to those of the human blood plasma. The present authors previously showed that the tantalum metal subjected to a NaOH treatment to form a sodium tantalate hydrogel layer on its surface forms the bonelike apatite on its surface in SBF in a short period. The gel layer as-formed on the metal is, however, not resistant against abrasion, and hence thus-treated metal is not useful for clinical applications. In the present study, effects of thermal treatment on the mechanical properties and apatite-forming ability of the NaOH-treated tantalum metal were investigated. The sodium tantalate gel on the NaOH-treated tantalum was dehydrated to convert into amorphous sodium tantalate by a thermal treatment at 300 °C in air environment and into crystalline sodium tantalates by the thermal treatment at 500 °C. Resistivity of the gel layer against both peeling-off and scratching was significantly improved by the thermal treatment at 300 °C. The high apatite-forming ability of the sodium tantalate hydrogel was a little decreased by the thermal treatment at 300 °C, but appreciably decreased by the thermal treatment at 500 °C. It is believed that the tantalum metal subjected to the 0.5 M-NaOH treatment and the subsequent thermal treatment at 300 °C is useful as implants in dental and orthopaedic fields, since it shows high bioactivity as well as high fracture toughness. © 2001 Kluwer Academic Publishers

Two kinds of water-swollen hydrogels composed of three monomers&sbd;poly(stearyl acrylate (C18A)-co-n-alkyl acrylates (CnA)-co-acrylic acid (AA)) and poly(16-acryloyloxyhexadecanoic acid (AHA)-co-CnA-co-AA) (n is the number of carbon atoms of side chains:  n = 14, 16, 18, 20, 22)&sbd;were synthesized, and their structures were investigated by wide-angle X-ray diffraction (WAXD) and small-angle X-ray diffraction (SAXD). Both gels formed the crystalline structure with the lamellae. In the case of poly(C18A-co-CnA-co-AA) gels, both the lamellar thickness, d2, and the melting temperature, Tm, increased with the increase in n, suggesting that C18A and CnA form molecularly mixed crystalline domains. On the other hand, d2 of poly(AHA-co-CnA-co-AA) gels was much smaller than that of poly(CnA-co-AA) gels, and Tm was constant regardless of n. An abrupt decrease in Tm was observed for poly(AHA-co-C18A-co-AA) gels at an AHA composition of 0.8. These results indicate that carboxyls attached at alkyl side chain end of AHA significantly shorten and stabilize the lamellae of the hydrogel due to the cooperative hydrogen bonding and rearrangement of the lamellar structure occurred.

Petrological studies on the surrounding metamorphic rocks of the Eppawala carbonatite body, Wanni complex, Sri Lanka, revealed that these rocks had been metamorphosed under amphibolite to granulite facies conditions. Garnet-sillimanite-biotite gneiss shows lower range of metamorphic temperature (730–770°C) than the migmatite gneiss (750–780°C) and the pressure varies from 6.6–7.8 kbar to 5.6–6.4 kbar respectively. The metamorphic age of the garnet-sillimanite-biotite gneiss and migmatite gneiss dated 607±23 Ma and 626±16 Ma, respectively for mineral — whole rock isochron in Sm-Nd system. These ages are compatible with the ages of regional high-grade metamorphism occurred 610–550 Ma in the three crustal units in Sri Lanka.

Deficiency of micronutrients, especially selenium, is common in critically ill patients. We investigated the micronutrient status (selenium, zinc, copper and manganese) and glutathione peroxidase (GSH-Px) activity in 30 tube-fed patients and 21 hospitalized non-tube-fed control patients. Serum levels of selenium, copper and manganese in tube-fed patients were significantly lower than in control patients (selenium: 4.85 ± 1.38 μg/dl versus 8.67 ± 1.45 μg/dl; copper: 44.7 ± 36.9 μg/dl versus 92.1 ± 21.2 μg/dl; manganese 0.59 ± 0.41 μg/dl versus 1.52 ± 0.59 μg/dl). However, zinc and log GSH-Px in the serum were similar in the two groups. Serum selenium concentration correlated with the daily intake of selenium in tube-fed patients, but zinc, copper and manganese concentrations did not correlate with the daily intake of the respective trace elements in tube-fed patients. Blood GSH-Px activity correlated positively with serum selenium concentrations in the control patients, but not in tube-fed patients. These results demonstrate that selenium content of enteral feed appears to be insufficient to maintain normal serum levels in elderly bedridden patients. Our findings emphasize the importance of monitoring micronutrient status in patients on enteral feeding to avoid trace element deficiencies