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Melamine toxicity is recognized as a distinct form of renal failure due to occlusion of the renal tubules by the compound melamine and its deaminated derivative, cyanuric acid. The morphology of melamine-cyanurate crystals in vivo differs from that in vitro, being rounded in the former case but needle-like in the latter. The reasons for this difference in morphology between in vivo and in vitro crystals remain unknown. In the present study, we investigated the in vitro effects of several possible intra-renal factors, i.e., pH and serum and urinary proteins, on the morphology of melamine-cyanurate crystals in order to clarify what might be responsible for the formation of rounded urolites in vivo. We found that serum proteins, such as fetal bovine serum, bovine serum albumin and bovine gamma-globulin, can alter the morphology of melamine cyanurate, turning it into rounded crystals. The urinary protein beta-2-microglobulin had a less pronounced effect. The crystal morphology was unaffected by pH. Based on the present in vitro findings and known clinical data, we suggest a putative protein-related model for melamine-cyanurate formation in the kidney.

Sputter deposited Cr-Mo alloy films have been investigated in electrical properties and microstructures. The resistivity of the films decreased with the Mo concentration from 20 to 40 at% and increased up to 80 at%Mo and showed lowest value at Mo film. This resistivity change was discussed with microstructure observations, XRD and recoiled Ar concentration. SEM and TEM images indicated that several grains were combined and form lager aggregated grains and columnar structure. Stress in the films was discussed also with relationship of Mo concentration. [doi:10.2320/matertrans.MRP2008206]

Bt plants are insect-resistant plants engineered to carry the gene coding the insecticidal protein of a soil bacterium, Bacillus thuringiensis. These transgenic plants provide a highly effective method of insect control and reduce dependence on pesticide chemicals. In consequence, they have provided higher yields, reduced crop mycotoxin levels because of the effective lowering of the insect damage, and have decreased the pesticide spraying work and cost. However, there are public concerns about the safety of Bt plants for humans, animals and the environment. This review describes recent research on the safety evaluation of Bt plants, focusing on our results in the toxicological studies of Bt11 corn.

Cry toxins produced by Bacillus thuringiensis are insecticidal toxins and have been recently introduced to genetically modified (GM) organisms. The toxins are considered harmless to humans and farm animals; however, it remains unclear whether the toxins affect the mammalian intestinal epithelium, the primary portal and absorption site after ingestion. Therefore, we performed immunohistochemical and ligand blot analyses using brush border membrane vesicles to investigate the interaction of Cry1Ab toxin, a popular Cry toxin developed in GM corn, with bovine intestinal epithelium, with special attention to the presence of Cry1Ab toxin-binding proteins of the epithelial cell. We found that Cry1Ab toxin binds to actin, a cytoskeletal protein. However, the toxin did not bind to aminopeptidase N, cadherin, or alkaline phosphatase, all of which are cell membrane receptors or candidate proteins necessary for the development of toxicity in susceptible insect cells. The present results and previous observations that Cry toxins have little acute toxicity on mammalian cells indicate that Cry1Ab toxin is able to bind to cytoskeletal actin, but that the bovine intestinal epithelial cell lacks membrane receptors, which are necessary for the toxin to exert its toxicity on the cell.

論文(Article)

Melamine-cyanurate (M-C) crystals, formed by melamine and cyanuric acid, are water-insoluble urolites that can cause renal tubule occlusion, leading to kidney failure. The morphology of the crystals in vivo differs from that in vitro, being rounded in the former case but needle-like in the latter. The reason for this difference remains unknown, but we have previously found that serum proteins, such as bovine serum albumin (BSA), can contribute to in vitro formation of rounded M-C crystals. In the present study, using scanning electron microscopy, we confirmed that, like BSA, polyvinylpyrrolidone (PVP), a synthetic macromolecule, can alter the crystal morphology to a spherical form. The size and surface structure differed between BSA- and PVP-induced M-C crystals.

The presence of maize intrinsic and recombinant crylAb genes in the gastrointestinal (GI) contents, peripheral blood mononuclear cells (PBMC), and visceral organs of calves fed genetically modified Btl 1 maize was examined by PCR in a subchronic 90-day performance study. Samples were collected from six Japanese Black/Holstein calves fed Bt 11 maize and from six calves fed non-Bt maize. Fragments of maize zein (Zel), invertase, chloroplast, and cty1Ab were detected inconsistently in the rumen fluid and rectal contents 5 and 18 h after feeding. The chloroplast DNA fragments of ribulose-1,5-bisphosphate carboxylase/oxygenase and tRNA were detected inconsistently in the PBMC, the visceral organs, and the longissimus muscle, while the crylAb gene was never detected in PBMC or in the visceral organs. These results suggest that feed-derived maize DNA was mostly degraded in the GI tract but that fragmented DNA was detectable in the GI contents as a possible source of transfer to calf tissues. These results also suggest that the recombinant crylAb genes were not transferred to the PBMC and tissues of calves fed Btl 1 maize.

7,8-Bis(benzyloxycarbonyl)-7,8-dicyanoquinodimethane (1d) was prepared successfully as isolable crystals at room temperature and determined to have an anti-form by 1H-NMR spectroscopy. When 1d was dissolved in basic polar solvents such as acetonitrile, acetone, tetrahydrofuran, dimethyl sulfoxide, and N,N-dimethylformamide, spontaneous polymerization took place to give polymers with Mn of 6 x 103 to 9.7 x 105. 1d is homopolymerizable with 2,2'-azobis(isobutyronitrile) (AIBN) as a radical initiator, triethylamine, proton sponge, and triphenylphosphine, but not with boron trifluoride diethyl etherate as a cationic initiator. 1d copolymerized with styrene (St) in the presence of AIBN in chloroform to obtain the monomer reactivity ratios r1 (1d) = 3.1 ± 0.5 and r2(St) = 0.030 ± 0.01 at 60 ° C, and Q and e values of 9.3 and + 0.73, respectively, indicating that 1d is highly conjugative and electron-accepting. The thermal behavior and photodegaradation for poly(1d) were investigated in comparison with the polym...

A high-tension annealing (HTA) method has been applied to nylon 66 fibres to improve their mechanical properties. The HTA was carried out three times under high tension close to the tensile strength at break. The nylon 66 fibre used for the HTA treatment was previously zone-drawn twice at 210°C under applied tensions of 14.5 MPa and 182.2 MPa. To orient amorphous chains selectively, two HTA treatments were carried out; the first HTA (HTA1) at 100°C under an applied tension of 143.3 MPa, and the second (HTA2) treatment at 110°C under 142.0 MPa. The third (HTA3) treatment was carried out at 190°C under 75.1 MPa to crystallize the amorphous regions oriented by the HTA1 and HTA2 treatments. The resulting HTA3 fibre had a draw ratio of 7.3, a value of birefringence of 0.0761, and a degree of crystallinity of 40.4%. The orientation factor of crystallites almost approached unity in the first high-temperature zone-drawing (HT-ZDI) stage, but that of amorphous regions (ƒa) was 0.575 in the HT-ZD1 stage. The ƒa increased with the processing and finally reached a high value of 0.852 for the HTA3 fibre. Dynamic moduli increased with the processing, and the dynamic modulus of the HTA3 fibre was 21.7 GPa at 25°C and 15.0 GPa even at 200°C.

Genetically modified corn Bt11 is insect-resistant and expresses Cry1Ab toxin, an insecticidal protein, in kernels. Although Bt11 corn is considered safe based on animal performance, there are no reports available on the clinico-biochemical effects of feeding it to cattle. In this study, we evaluated the effects of feeding Bt11 to calves, using blood and ruminal clinico-biochemical parameters. Our three-month-long feeding experiment demonstrated that calves (n=6), fed with a ration containing 43.3% of Bt11 corn kernels as dry matter, did not develop any discernible clinical, hematological, biochemical, or ruminal abnormalities as compared with control calves (n=6) fed non-Bt11 corn. The results suggest that the transgenic Bt11 has no negative clinico-biochemical effects on calves.

The effects of sera from calves receiving Burdizzo castration or intravenous ACTH injection (100 IU a head) and then developing an acute plasma cortisol rise on the bovine lymphocyte and neutrophil function were examined with a view to elucidating whether these treatments can induce the animals to develop a serum immunomodulatory effect on those cells. When incubated with bovine lymphocytes, the sera from ACTH-treated calves induced a significant suppression (p

We measured the concentrations of S-100B, a marker protein used in humans to detect brain damage, in the cerebrospinal fluid (CSF) of clinically normal cattle (n=15, mean age +/- SD: 31.8 +/- 37.5 months) and of cattle with various inflammatory disorders (n=43, 70.6 +/- 31.9 months). The mean +/- SD CSF S-100B level was 2.9 +/- 1.6 ng/ml in the normal group and 7.0 +/- 7.4 ng/ml in the diseased group. Thirteen diseased cattle that had developed no obvious neurological signs showed abnormally high S-100B concentrations (8.0 ng/ml), whereas the two cattle with neurological disorders did not. No particular disease could be related to the S-100B rise. Therefore, it remains inconclusive whether measurement of CSF S-100B concentration is useful in veterinary neurological diagnosis.

Melamine-cyanurate (M-C) crystals, formed by melamine and cyanuric acid, are water-insoluble urolites that can cause renal tubule occlusion, leading to kidney failure. The morphology of the crystals in vivo differs from that in vitro, being rounded in the former case but needle-like in the latter. The reason for this difference remains unknown, but we have previously found that serum proteins, such as bovine serum albumin (BSA), can contribute to in vitro formation of rounded M-C crystals. In the present study, using scanning electron microscopy, we confirmed that, like BSA, polyvinylpyrrolidone (PVP), a synthetic macromolecule, can alter the crystal morphology to a spherical form. The size and surface structure differed between BSA- and PVP-induced M-C crystals.

Melamine toxicity is recognized as a distinct form of renal failure due to occlusion of the renal tubules by the compound melamine and its deaminated derivative, cyanuric acid. The morphology of melamine-cyanurate crystals in vivo differs from that in vitro, being rounded in the former case but needle-like in the latter. The reasons for this difference in morphology between in vivo and in vitro crystals remain unknown. In the present study, we investigated the in vitro effects of several possible intra-renal factors, i.e., pH and serum and urinary proteins, on the morphology of melamine-cyanurate crystals in order to clarify what might be responsible for the formation of rounded urolites in vivo. We found that serum proteins, such as fetal bovine serum, bovine serum albumin and bovine gamma-globulin, can alter the morphology of melamine cyanurate, turning it into rounded crystals. The urinary protein beta-2-microglobulin had a less pronounced effect. The crystal morphology was unaffected by pH. Based on the present in vitro findings and known clinical data, we suggest a putative protein-related model for melamine-cyanurate formation in the kidney.

Void fractions in a simulated pressurized water reactor (PWR) core rod bundle geometry were measured under boil-off conditions covering pressures from 3 to 12 MPa and mass fluxes from 5 to 100 kg m −2 s −1 , with a particular interest in void fractions at higher pressures and relatively high mass fluxes. Test results showed that the Chexal-Lellouche model predicts best the present (volume-averaged) void-fraction data among correlations and models examined in this study. The volume-averaged void fractions obtained from differential pressure measurements are systematically smaller than the chordally averaged void fractions obtained from gamma densitometer measurements. Local void fractions were measured in the same bundle for non-heated steam-water two-phase flow of 3 MPa by using an optical void probe. It was found that the difference between the volume-averaged and chordally averaged void fractions mentioned above can be explained qualitatively by a local void-fraction distribution in the bundle measured in the latter tests.

The corrosion behavior of three kinds of sputter-deposited Co-base alloy thin films—whose compositions are almost the same as those of the currently used magnetic recording hard disks—has been studied by electrochemical methods and X-ray photoelectron spectroscopy analysis. The alloys suffer general corrosion in a 0.5 M NaCl solution and pitting during anodic polarization in borate-boric acid solutions containing Cl − ions with pH 8.4 at 30 °C. The corrosion resistance decreases in the following order: Co12Cr2 Ta >Co24Ni5Cr⪢ Co1 o Pt 9Ni. The high corrosion resistance of the Co12Cr2Ta alloy film is based on the formation of a Cr- and Ta-enriched surface film. The C overcoat is incomplete and it may enhance localized corrosion through pores in the overcoat, as a result of the galvanic interaction between electrically conductive C and Co-base alloy films.

Seven miniature pigs were injected intravenously with deoxynivalenol (DON) at 1 mg/kg body weight; afterward, the number of leukocytes in peripheral blood, the luminol-dependent chemiluminescence of neutrophils, the serum or plasma concentration of cytokines and acute-phase proteins were evaluated to determine the effects of acute exposure to DON on inflammatory responses. White blood cell counts were transiently increased at 3, 6, and 12 hr post-injection (PI) due to the increased number of neutrophils. The luminol-dependent chemiluminescence value of neutrophils was significantly elevated at 24 hr PI, indicating the activation of the bactericidal function of neutrophils. Significant increases of interleukin (IL)-8 and tumor necrosis factor-α at 3 hr PI and IL-6 at 6 hr PI were detected in the serum. The concentration of haptoglobin and serum amyloid A was significantly increased at 24 hr PI. These results suggest that acute exposure to DON induced a temporary recruitment of neutrophils in the peripheral blood by IL-8 and subsequent activation of the bactericidal function, and a transient increase of proinflammatory cytokines and acute-phase proteins, indicating the immunomodulatory effects of DON in pigs.

High-density recording requires longitudinal magnetic recording media with high coercivity and low noise. We report our studies of magnetic and microstructural properties of high-coersivity CoCrTa films. A coercivity of 2450 Oe has been obtained by applying a high bias voltage to the substrate. Microstructural analysis by TEM and electron diffraction studies revealed that in high-coercivity film c-axes are strongly oriented in the film plane.

Visual observation of high-pressure, high-temperature steam/water two-phase flow is of interest for many engineering applications. It is particularly so when complicated phase-change and phase separation/mixing processes are involved. This paper is concerned with development of cooling-free small-sized video probes which withstands high-pressure steam/water two-phase flow. The probe uses optical glass fiber for both lighting and observation. To obtain a clear image, several technical problems were resolved, including light intensity, window material corrosion and thermal expansion. These are discussed in relation to practical experiences with experimental facilities which simulate thermal-hydraulics condition during a loss-of-coolant accident (LOCA) of a pressurized water reactor (PWR) at pressures ranging up to 18MPa and temperatures up to 630K.

Natural convection in a heated horizontal fluid layer have been studied experimentally and theoretically for many years. In industrial components such as boilers or reactors, heat and mass are sometimes transferred through a horizontal fluid layer, including the internal structures. The heat transfer characteristics was experimantally studied in the horizontal water layer, including honeycombs of different flow area reduction ratios. Large eddy motion was reduced with the honeycomb but the heat transfer rate through the layer could not be affected, even at the flow area reduction rate of 0.09. Further reduction of the flow area resulted in the nonuniform temperature distribution of the central fluid layer and depression of the heat transfer rate.

Among the elderly, hip fracture is the most common outcome of osteoporosis. The main aim of this study was to investigate the clinical characteristics, treatment, complications, long-term outcome and mortality of elderly hip fracture patients, aged 90 years and over. MATERIAL AND METHODS: We retrospectively analyzed 44 patients admitted between 1994 and 1998 with femoral neck or trochanteric fracture. The age of the patients ranged between 90 and 99 years and all 44 patients were surgically managed with one exception who died during the preoperative hospitalization. Hemiarthroplasty was most often used for medial (subcapital and transcervical) fractures. Internal fixation with either Ender nails or a compression hip-screw with a plate was used for lateral (per-, inter- and sub- trochanteric) fractures. RESULTS AND CONCLUSIONS: Most fractures (98%) were due to low energy trauma. Overall, mortality was 29.6% during the first year, being higher in patients with greater severity of pre-existing medical illness and in patients with difficulty in walking before the operation. In addition, if hemiarthroplasty was performed, the rate of death was higher. Rehabilitation was difficult if the patient had severe dementia or had difficulty in walking before the operation.

We evaluated the immunotoxicity of deoxynivalenol (DON), a Fusarium mycotoxin, on bovine and porcine neutrophils in vitro by using two function parameters, luminol-dependent chemiluminescence and random migration under agarose. A 2-hr DON treatment suppressed the chemiluminescence of bovine and porcine cells by 42% and 35% (on average) at 10(-5)M, and by 19% and 26% at 10(-6)M. Slight suppression was observed at concentrations lower than 10(-6)M. However, after an 18-hr DON treatment, random migration of neutrophils of both species remained unaffected, even at the highest concentration (10(-5)M). Although further extensive studies are needed, to our knowledge this is the first study to have revealed in vitro that DON can affect neutrophil function.

Healthy calves were subjected to transportation by road for 48 hours. Serum collected from each calf prior to departure and upon completion of transport was incubated with peripheral blood neutrophils from a clinically healthy calf. Thereafter, the activity of zymosan-induced chemiluminescence, an indicator of bactericidal function, of the incubated cells was examined. A significant decrease in activity was observed in the cells incubated with the sera after transport. This suggests that sera after transportation might have an immunosuppressive function on peripheral blood neutrophils.

The Cry proteins produced by Bacillus thuringiensis are considered to be highly specific insecticidal proteins. Judged to be safe for humans and farm animals due to their insect-oriented selective toxicity, the proteins have been utilized as a biological pesticide and introduced into genetically modified plants. However, some critical fundamental characters of the Cry proteins remain unclear, and the direct effects of activated Cry proteins on mammalian cells have not yet been fully confirmed. Therefore, in this study we employed primary cultured bovine hapatocytes as a model system to determine if Cry1Ab, a Cry protein, affects mammalian cells. There were no significant changes in the secretion of albumin or the morphology of the Cry1Ab-treated cells. The LDH release showed a tendency to increase after the administration of Cry1Ab, but not significantly. Taking these results on bovine hepatocytes into consideration, Cry1Ab has little acute toxicity on mammalian cells.

We evaluated the effects of short-term (up to 60 min) irradiation of corn silage with ultraviolet (UV) light (intensity: 1.5 mW/cm(2) at 254 nm UV-C wavelength), along with constant stirring of the silage, on the concentration of deoxynivalenol (DON), a major feed-contaminating mycotoxin, and those of α-tocopherol (vitamin E) and β-carotene (pro-vitamin A). The initial DON concentration in artificially contaminated silage was set at approximately 60 µg/g dry silage weight. After irradiation, the level of DON was decreased significantly (P0.05) by approximately 13 µg/g (22%) on average at 30 min, and by 12 µg/g (21%) at 60 min. However, the concentrations of the vitamins remained relatively unaffected. Although further improvement is needed, short-term UV irradiation seems a promising on-farm method for reducing the level of DON in feedstuffs.

The effect of ammonia inhalation on the luminol-dependent chemiluminescence response of bronchoalveolar lavage (BAL) cells was investigated in clinically normal calves receiving eight ml of ammonia water (5,000 ppm) in the form of aerosol sprayed into the nasal cavities (four ml into each nostril) once a day for two weeks. The chemiluminescence level of BAL cells was augmented following the sprayings of ammonia compared with prior to exposure. The level still remained high one week after the exposure was removed, but showed recovery after two weeks.

Six 1-month-old piglets were intravenously injected with deoxynivalenol (DON) at the concentration of 1 mg/kg body weight, with three pigs each necropsied at 6 and 24 h post-injection (PI) for investigation of hepatotoxicity and immunotoxicity with special attention to apoptotic changes and cytokine mRNA expression. Histopathological examination of the DON-injected pigs revealed systemic apoptosis of lymphocytes in lymphoid tissues and hepatocytes. Apoptosis of lymphocytes and hepatocytes was confirmed by the TdT-mediated dUTP-biotin nick end-labeling (TUNEL) method and immunohistochemical staining against singlestranded DNA and cleaved caspase-3. The number of TUNELpositive cells in the thymus and Peyer's patches of the ileum was increased at 24 h PI compared to 6 h PI, but the peak was at 6 h PI in the liver. The mRNA expression of interleukin (IL)-1beta, IL-6, IL-18, and tumor necrosis factor (TNF)-alpha in the spleen, thymus and mesenteric lymph nodes were determined by semi-quantitative RT-PCR, and elevated expression of IL-1beta mRNA at 6 h PI and a decrease of IL-18 mRNA at 24 h PI were observed in the spleen. IL-1beta and IL-6 mRNA expressions increased significantly at 6 h PI in the thymus, but TNF-alpha decreased at 6 h PI in the mesenteric lymph nodes. These results show the apoptosis of hepatocytes suggesting the hepatotoxic potential of DON, in addition to an immunotoxic effect on the modulation of proinflammatory cytokine genes in lymphoid organs with extensive apoptosis of lymphocytes induced by acute exposure to DON in pigs.

The mammalian intestinal epithelium has been found, based on in vivo experiments, to be resistant to insecticidal Cry toxins, which are derived from Bacillus thuringiensis and fatally damage insect midgut cells. Thus, the toxins are commonly used as a genetic resource in insect-resistant transgenic plants for feed. However, Cry toxins bind to the cellular brush border membrane vesicle (BBMV) of mammalian intestinal cells. In this study, we investigated the affinity of Cry1Ab toxin, a lepidopteran-specific Cry1-type toxin, to the cellular BBMV of two mammalian intestinal cells as well as the effect of the toxin on the membrane potential of three mammalian intestinal cells compared to its effects on the silkworm midgut cell. We found that Cry1Ab toxin did bind to the bovine and porcine BBMV, but far more weakly than it did to the silkworm midgut BBMV. Furthermore, although the silkworm midgut cells developed severe membrane potential changes within 1 h following the toxin treatment at a final concentration of 2 mug/ml, no such membraneous changes were observed on the bovine, porcine, and human intestinal cells. The present in vitro results suggest that, although Cry1Ab toxin may bind weakly or nonspecifically to certain BBMV components in the mammalian intestinal cell, it does not damage the cell's membrane integrity, thus exerting no subsequent adverse effects on the cell.

The chemiluminescence response of cervine neutrophils to various stimuli was investigated in comparison with that of bovine and human homologues. The cervine cells showed a strong and consistent response, as observed in other species, to opsonized zymosan, phorbol myristate acetate and concanavalin A. The cells, however, like bovine homologues, failed to respond to n-formyl-methionyl-leucyl-phenylalanine which is a potent stimulant of human neutrophils.