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Intracellular and extracellular catalases of different species of Candida were investigated using different culture media. All the Candida strains produced intracellular catalase, whose enzymatic activity was detected by non-denaturating polyacrylamide gradient (4-30%) gel electrophoresis. The cell extracts presented a major 230 kDa catalase band and in some strains variants of catalase with different molecular weights were detected. Candida catalase activity was not affected by heating at 50 degrees C and incubation with beta-mercaptoethanol, but treatment with sodium dodecyl sulphate inhibited or reduced enzymatic activity. Extracellular enzyme activity was not detected in any of the culture filtrate extracts tested.

Primary human cord blood mononuclear cells (CB MNCs) were inoculated into layers of primary human bone marrow stromal cells prepared in a nonwoven fabric porous carrier [three dimensional (3-D)] or on a dish [two dimensional (2-D)] using a cytokine-free medium and were cultured for 7 days with or without the addition of heparin. The number of progenitor cells increased threefold during the 3-D coculture, whereas it decreased in the 2-D culture. Heparin addition to the 3-D coculture further increased the number of progenitors twofold, whereas the addition of desulfated heparin had no effect. The heparin effect was also observed in a 3-D culture of CB MNCs without stromal cells when conditioned medium was employed. The coating of the carrier with N-(O-beta-(6-O-sulfogalactopyranosyl)-6-oxyhexyl)-3,5-bis (dodecyloxy)-benzamide instead of heparin addition also increased the number of progenitor cells in the 3-D culture of CB MNCs without stromal cells when the conditioned medium was employed. The 3-D coculture constructed with nonwoven fabrics and stromal cells was clearly superior to the 2-D culture because of the expansion of CB hematopoietic progenitor cells without cytokine addition. Heparin addition to the 3-D coculture further increased the number of progenitor cells, which may result from a synergistic effect of soluble cytokines produced by stromal cells with the sulfur group of heparin.

The magnetic properties of nanocrystalline hard magnetic and soft magnetic are summarized. When the grain size becomes of the order f the magnetic exchange length exchange coupling occurs. The different concepts of exchange coupling in these materials are discussed. Exchange coupling leads in isotropic hard magnetic materials to a remanence enhancement. Soft magnetic materials exhibit due to exchange coupling a lower coercivity, lower losses and consequently also improved properties.

The sleep EEGs and fatigue of 9 female family caregivers (age M = 65 yr.) and 9 female noncaregivers (age M = 67 yr.) were measured during two successive nights at their houses. Perceived quality of sleep was measured by the Sleep Evaluation Questionnaire. Fatigue was measured by a self-rated questionnaire, the Perceived Symptoms of Fatigue, and by critical flicker fusion (CFF) frequency. The caregivers had a significantly higher percentage of Stage 1 and a lower percentage of Stage 2 during the 2nd cycle and a higher percentage of Stages 3+4 during the 3rd cycle than those of the noncaregivers. Caregivers had significantly higher percentages of EEG waves of 7–9 Hz in the 1st cycle and 6–9 Hz in the 2nd cycle and significantly lower percentages of 2–3 Hz in the 1st cycle than those of the noncaregivers. The caregivers reported a lower quality of sleep and higher perceived fatigue symptoms and also lower CFF frequency (increased physiological fatigue) than noncaregivers. The caregivers' sleep EEGs were associated with their higher sleep needs and fatigue.

A system for magnetic characterization of soft magnetic materials in low field is described. Fields of 0.02 A/m can be applied and a good sensibility is achieved by means of a Lock-In amplifier. Signals of 1 nV can be measured, and magnetic characterization with external stresses can be made. The measurements can be done from room temperature up to 973 K. The system allows to perform permeability, pinning field, Curie temperature and disaccommodation measurements automatically. >

Efficient preparation of lipid analogues is described in which various long alkoxy chains and 2-hydroxyethyl group were covalently linked with benzoic acid derivatives. An alpha-mannopyranosyl group was stereoselectively introduced by the conventional imidate method into the terminal hydroxy group without any alternation of other moieties in a molecule. The resulting new glycoconjugates acted as models of natural glycolipids for protein-carbohydrate interactions.

Previous prospective studies have raised the possibility that the antioxidantproperties of carotenoids and vitamin E (alpha-tocopherol) and the role of vitamin A (retinol) in cellular differentiation may be associated with a reduced risk of subsequent breast cancer. To investigate the association between serum and plasma concentrations of retinol, retinyl palmitate, alpha-carotene, beta-carotene, beta-cryptoxanthin, lutein, lycopene, total-carotenoids, alpha-tocopherol, and gamma-tocopherol with subsequent development of breast cancer, a nested case control study was conducted among female residents of Washington County, Maryland, who had donated blood for a serum bank in 1974 or 1989. Cases (n = 295) and controls (n = 295) were matched on age, race, menopausal status, and date of blood donation, and the analyses were stratified by cohort participation. Median concentrations of beta-carotene, lycopene, and total carotene were significantly lower in cases compared with controls in the 1974 cohort (13.1, 12.5, and 7.9% difference; P = 0.01, 0.04, and 0.04, respectively) and for lutein in the 1989 cohort (6.7% difference; P = 0.02). The risk of developing breast cancer in the highest fifth was approximately half of that of women in the lowest fifth for beta-carotene [odds ratio (OR) = 0.41; 95% confidence interval (CI) 0.22-0.79; P trend = 0.007], lycopene (OR = 0.55; 95% CI 0.29-1.06; P trend = 0.04), and total carotene (OR = 0.55; 95% CI 0.29-1.03; P trend = 0.02) in the 1974 cohort. There was generally a protective association for other micronutrients in both cohorts, although none reached statistical significance. The results suggest that carotenoids may protect against the development of breast cancer.

A high-performance and rapid chemiluminescence immunoassay for model food allergen lysozyme, one of the major allergenic components in egg white, using antibody-conjugated bacterial magnetic particles and a fully automated system was developed. This system contains a reaction station, tip rack, and an eight-tip pipettor that is able to attach and detach a strong magnet to the tip surface. The immunoreaction time was shortened to 5 min, and the assay was completed within 20 min. The lower detection limit for lysozyme was 10 ng/mL. This system can be used to perform 24 samples in 60 min within 10% coefficient of variation.

Synthesis of CMP-deaminoneuraminic acid (CMP-beta-D-Kdn) and its enzymatic transfer reaction using bacterial alpha-(2--6)-sialyltransferase were examined. CMP-beta-D-Kdn was prepared from methyl 4,5,7,8,9-penta-O-acetyl-3-deoxy-D-glycero-beta-D-galacto-2- nonulopyranosonate (2) in 24% overall yield. Enzymatic synthesis of Kdn oligosaccharide with CMP-beta-D-Kdn (10.2 mumol), methyl beta-D-lactosaminide (7, 8.1 mumol) and purified sialyltransferase (80 munits) afforded Kdn-alpha-(2--6)-Gal-beta-(1--4)-GlcNAc-beta-1-OMe in 77% yield.

Neurons are highly polarized cells composed of dendrites, cell bodies, and long axons. Because of the lack of protein synthesis machinery in axons, materials required in axons and synapses have to be transported down the axons after synthesis in the cell body. Fast anterograde transport conveys different kinds of membranous organelles such as mitochondria and precursors of synaptic vesicles and axonal membranes, while organelles such as endosomes and autophagic prelysosomal organelles are conveyed retrogradely. Although kinesin and dynein have been identified as good candidates for microtubule-based anterograde and retrograde transporters, respectively, the existence of other motors for performing these complex axonal transports seems quite likely. Here we characterized a new member of the kinesin super-family, KIF3A (50-nm rod with globular head and tail), and found that it is localized in neurons, associated with membrane organelle fractions, and accumulates with anterogradely moving membrane organelles after ligation of peripheral nerves. Furthermore, native KIF3A (a complex of 80/85 KIF3A heavy chain and a 95-kD polypeptide) revealed microtubule gliding activity and baculovirus-expressed KIF3A heavy chain demonstrated microtubule plus end-directed (anterograde) motility in vitro. These findings strongly suggest that KIF3A is a new motor protein for the anterograde fast axonal transport.

In order to investigate the effect of boron additions in the magnetostrictive behavior of Fe72Ga28 alloy, this alloy was doped with 0.5, 1.0, 1.5 and 2.0 at.% of boron. The results have shown that boron additions of 0.5 and 1.0% improve significantly the magnetostriction, the values being about two-fold higher compared to the undoped alloy. Microstructural evaluations suggest that boron additions suppress partially the D03 phase ordering, retaining the α-phase. Furthermore, the increase of lattice parameters of the α and D03 phases indicates that boron enters interstitially in the cubic lattice of these phases. Both effects are considered to be responsible for the increased magnetostriction observed in the (Fe0.72Ga0.28)99.5B0.5 and Fe0.72Ga0.28)99.0B1.0 alloys.

One-dimensional diffusion of microtubules (MTs), a back-and-forth motion of MTs due to thermal diffusion, was reported in dynein motility assay. The interaction between MTs and dynein that allows such motion was implicated in its importance in the force generating cycle of dynein ATPase cycle. However, it was not known whether the phenomenon is special to motor proteins. Here we show two independent examples of one-dimensional diffusion of MTs in the absence of motor proteins. Dynamin, a MT-activated GTPase, causes a nucleotide dependent back-and-forth movement of single MT up to 1 micron along the longitudinal axes, although the MT never showed unidirectional consistent movement. Quantitative analysis of the motion and its nucleotide condition indicates that the motion is due to a thermal driven diffusion, restricted to one dimension, under the weak interaction between MT and dynamin. However, specific protein-protein interaction is not essential for the motion, because similar back-and-forth movement of MT was achieved on coverslips coated with only 0.8% methylcellulose. Both cases demonstrate that thermal diffusion could provide a considerable sliding of MTs only if MTs are restricted on the surface appropriately.

The structure of annealed Sm(Co0.6Cu0.4)5 compounds, prepared with different Sm excess content, has been investigated by means of high resolution x-ray diffraction and scanning electron microscopy. The samples were also magnetically characterized by thermomagnetic analysis and M versus H curves at room temperature. Increasing Sm excess improves the compositional order of the 1?:?5 phase. The coercivity (HC) and the Curie temperature (TC) are both changed as a function of Sm excess content. The decrease in the structural defects density, resulting from the compositional order, is responsible for the observed magnetic behaviour.

Brain dynein is a microtubule-activated ATPase considered to be a candidate to function as a molecular motor to transport membranous organelles retrogradely in the axon. To determine whether brain dynein really binds to retrogradely transported organelles in vivo and how it is transported to the nerve terminals, we studied the localization of brain dynein in axons after the ligation of peripheral nerves by light and electron microscopic immunocytochemistry using affinity-purified anti-brain dynein antibodies. Different classes of organelles preferentially accumulated at the regions proximal and distal to the ligated part. Interestingly, brain dynein accumulated both at the regions proximal and distal to the ligation sites and localized not only on retrogradely transported membranous organelles but also on anterogradely transported ones. This is the first evidence to show that brain dynein associates with retrogradely transported organelles in vivo and that brain dynein is transported to the nerve terminal by fast flow. This also suggests that there may be some mechanism that activates brain dynein only for retrograde transport.

The techniques of pre- and post-embedding immunocolloidal gold electron microscopy were tested for their usefulness for analyzing the morphogenesis of human immunodeficiency virus (HIV) strain LAV employing U-937 cells persistently infected with the virus (U-937/LAV). By both techniques the following results were obtained. (1) Budding process was restricted to a localized area at the membrane adjacent to the Golgi apparatus. (2) The distribution of viral envelope antigens was restricted to the electron-dense crescent structures on the cell surface. (3) Virions released from the cells could be classified mainly into 2 categories: virions with doughnut-shaped cores or with conical cores at the center of the particles. And p24 proteins localized on the thick electron-dense cores of both types. These findings support the idea that pre- and post-embedding immunogold electron microscopy is very useful for studying the morphogenesis of viruses.

A measurement method for studying the magnetoelectric effect in pulsed magnetic fields was developed. Besides magnetization, the system allows the measurement of magnetostriction (using strain gauges) and the magnetoelectric effect. For measuring the magnetoelectric effect a special sample holder with fixed contacts and compensation coils was developed to ensure the reproducibility of the measurements. The magnetoelectric effect can be measured by two different methods: (i) During the application of a magnetic field pulse when the voltage appearing on the sample is directly recorded and (ii) As a function of a high frequency (f=10kHz) ac field superimposed to the main field pulse. In this way an ac voltage appears in the sample which is proportional to the charge change ΔQ=Q0sin(wt+Φ). This voltage is measured using a fast analog lock-in amplifier. A detailed description of the total system is provided. The magnetoelectric effect on well known composites of cobalt ferrite and barium titanate was measured ...

The human astrocytoma cell line U87-MG expressed two major basic fibroblast growth factor (FGF) mRNA transcripts of 7.0 and 3.7 kilobase (kb), as well as several low abundance transcripts of lower mol wt (1.0-1.8 kb). The phorbol ester phorbol-12,13-dibutyrate caused a time- and dose-dependent increase in the abundance of basic FGF mRNA transcripts. At a concentration of 1 microM, phorbol ester increased the level of both the 7.0 and 3.7 kb transcripts within 4 h, reached a plateau at 1.5- to 2.5-fold above control levels by 6 h and remained elevated for at least 12 h. When measured at 6 h after drug addition, the abundance of both 7.0 and 3.7 kb transcripts was maximally stimulated by 100 nM phorbol ester (EC50 = 10-20 nM). FGF mRNA levels were also stimulated to a similar extent by platelet-derived growth factor (0.15-5 U/ml) or the synthetic diacylglycerol analog 1-oleoyl-2-acetyl-rac glycerol (1-300 nM) at doses which stimulated DNA synthesis in these cells. Neither (Bu)2cAMP (0.03-2 mM) nor A23187 (0.3-1000 nM) had any effect on FGF expression. When U87-MG cells were exposed to phorbol ester for 24 h several differences were observed: the dose response curve was shifted to the left (EC50 = 3-5 nM; maximum response at 10 nM phorbol ester) and the response of the 7.0 and 3.7 kb transcripts was attenuated at higher doses (100-1000 nM), perhaps reflecting down-regulation of protein kinase C by the phorbol ester.(ABSTRACT TRUNCATED AT 250 WORDS)

Lumi-aggregometerを用いて血小板より放出されるATP量を求め, 虚血性脳血管障害におけるATP放出能と凝集能との関係ならびに抗血小板剤の効果について検討した.抗血小板剤未投与の脳血栓症, TIAのATP放出量はそれぞれ3.88±2.24μM, 4.97±4.11μMであった.最大凝集率 (M%) はそれぞれ66.3±11.1%, 77.1±11.6%, 最大凝集までの時間 (Tm) はそれぞれ288.5±86.9sec, 301.8±78.8sec, 解離率 (D%) はそれぞれ, 6.2±11.5%, 3.4±5.1%であった.これらの値は, 健康成人ならびにASA (0.3～0.7g/日), ticlopidine100mg/日または200mg/日の治療群と比べ有意 (p

We report measurement of the luminescence spectra of highly photoexcited semiconductor samples of GaAs, CdTe and InP. The experiments were performed under similar conditions as those imposed on the systems in previous work devoted to the observation of inelastic (Doppler - Raman) scattering of light. We show that our results are fully consistent with the interpretation of the macroscopic thermodynamic state of the system in terms of a hot excitation model.

東北地方における都市, 農業地域, 漁業地域の婦人の食行動および食習慣を, 家族形態別に分類し, 核家族1,006名, 拡大家族1,147名について検討し, 次の結果を得た。1) 家族の共食頻度は, 夕食で拡大家族に多くみられた。食事内容は, 80%以上が主, 副食ともに同じとし, 拡大家族では副食を異にする場合が多かった。2) 出前, 家族揃っての外食の頻度は, 核家族が有意に高かった。それらの理由の多くは, 出前では,“来客があった時”で,特に拡大家族に多く, 外食では“家族の団らんを目的とした時”,“家族の誕生日”とし, 核家族が有意に多かった。3) 欠食については, 3地域平均で“ほとんどしない”が拡大家族に多かった。欠食の理由は“時間がない”,“食欲がない”で核家族に多い傾向がみられ,“習慣”は拡大家族に多かった。4) 米飯, 味噌汁, 漬け物の摂取頻度は, 3地域平均で拡大家族が有意に高く, 特に農業, 漁業地域で顕著であった。5) 肉類は, いずれも核家族が多く摂取していた。魚肉加工品は, 3地域平均で拡大家族が多く, 地域別では, 農業地域で目立った。6) 野菜類の摂取頻度は, 拡大家族がやや高かった。その調理手法では, 核家族で“生のまま”,“妙める”が有意に高く, 拡大家族で多いのは“煮る”だけであった。7) 3地域平均で食行動, 食習慣ともに核家族は現代的傾向が, 拡大家族は保守的傾向が強かった。地域別でも同様であったが, 都市では大きな差はなく, 農業地域はいずれも最も保守的であった。