Prediction of the superimposed laser shot number for copper using a deep convolutional neural network

Image-based deep learning (IBDL) is an advanced technique for predicting the surface irradiation conditions of laser surface processing technology. In pulsed-laser surface processing techniques, the number of superimposed laser shots is one of the fundamental and essential parameters that should be optimized for each material. Our primary research aims to build an adequate dataset using laser-irradiated surface images and to successfully predict the number of superimposed shots using the pre-trained deep convolutional neural network (CNN) models. First, the laser shot experiments were performed on copper targets using a nanosecond YAG laser with a wavelength of 532 nm. Then, the training data were obtained with the different superimposed shots of 1 to 1024 in powers of 2. After that, we used several pre-trained deep CNN models to predict the number of superimposed laser shots. Based on the dataset with 1936 images, VGG16 shows a high validation accuracy, higher sensitivity, and more than 99% precision than other deep CNN models. Utilizing the VGG16 model with high sensitivity could positively impact the industries' time, efficiency, and overall production.

Direct observation of imploded core heating via fast electrons with super-penetration scheme

Fast ignition (FI) is a promising approach for high-energy-gain inertial confinement fusion in the laboratory. To achieve ignition, the energy of a short-pulse laser is required to be delivered efficiently to the pre-compressed fuel core via a high-energy electron beam. Therefore, understanding the transport and energy deposition of this electron beam inside the pre-compressed core is the key for FI. Here we report on the direct observation of the electron beam transport and deposition in a compressed core through the stimulated Cu Kα emission in the super-penetration scheme. Simulations reproducing the experimental measurements indicate that, at the time of peak compression, about 1% of the short-pulse energy is coupled to a relatively low-density core with a radius of 70 μm. Analysis with the support of 2D particle-in-cell simulations uncovers the key factors improving this coupling efficiency. Our findings are of critical importance for optimizing FI experiments in a super-penetration scheme.

Assessing infrared intensity using the evaporation rate of liquid hydrogen inside a cryogenic integrating sphere for laser fusion targets

Infrared (IR) heating processes have been studied to form a deuterium layer in an inertial confinement fusion target. To understand the relationship between the IR intensity and the fuel layering time constant, we have developed a new method to assess the IR intensity during irradiation. In our method, a glass flask acting as a dummy target is filled with liquid hydrogen (LH₂) and is then irradiated with 2-μm light. The IR intensity is subsequently calculated from the time constant of the LH₂ evaporation rate. Although LH₂ evaporation is also caused by the heat inflow from the surroundings and by the background heat, the evaporation rate due to IR heating can be accurately determined by acquiring the time constant with and without irradiation. The experimentally measured IR intensity is 0.66 mW/cm², which agrees well with a value estimated by considering the IR photon energy balance. Our results suggest that the present method can be used to measure the IR intensity inside a cryogenic system during IR irradiation of laser fusion targets.

Boosting laser-ion acceleration with multi-picosecond pulses

Using one of the world most powerful laser facility, we demonstrate for the first time that high-contrast multi-picosecond pulses are advantageous for proton acceleration. By extending the pulse duration from 1.5 to 6 ps with fixed laser intensity of 1018 W cm-2, the maximum proton energy is improved more than twice (from 13 to 33 MeV). At the same time, laser-energy conversion efficiency into the MeV protons is enhanced with an order of magnitude, achieving 5% for protons above 6 MeV with the 6 ps pulse duration. The proton energies observed are discussed using a plasma expansion model newly developed that takes the electron temperature evolution beyond the ponderomotive energy in the over picoseconds interaction into account. The present results are quite encouraging for realizing ion-driven fast ignition and novel ion beamlines.

X-ray polarization spectroscopy to study anisotropic velocity distribution of hot electrons produced by an ultra-high-intensity laser

The anisotropy of the hot-electron velocity distribution in ultra-high-intensity laser produced plasma was studied with x-ray polarization spectroscopy using multilayer planar targets including x-ray emission tracer in the middle layer. This measurement serves as a diagnostic for hot-electron transport from the laser-plasma interaction region to the overdense region where drastic changes in the isotropy of the electron velocity distribution are observed. These polarization degrees are consistent with analysis of a three-dimensional polarization spectroscopy model coupled with particle-in-cell simulations. Electron velocity distribution in the underdense region is affected by the electric field of the laser and that in the overdense region becomes wider with increase in the tracer depth. A full-angular spread in the overdense region of 22.4 degrees -2.4+5.4 was obtained from the measured polarization degree.

Experimental evidence of impact ignition: 100-fold increase of neutron yield by impactor collision

We performed integrated experiments on impact ignition, in which a portion of a deuterated polystyrene (CD) shell was accelerated to about 600 km/s and was collided with precompressed CD fuel. The kinetic energy of the impactor was efficiently converted into thermal energy generating a temperature of about 1.6 keV. We achieved a two-order-of-magnitude increase in the neutron yield by optimizing the timing of the impact collision, demonstrating the high potential of impact ignition for fusion energy production.

Laser ion acceleration via control of the near-critical density target

Duration-controlled amplified spontaneous emission with an intensity of 10(13) W/cm(2) is used to convert a 7.5-microm -thick polyimide foil into a near-critical plasma, in which the p -polarized, 45-fs , 10(19) -Wcm (2) laser pulse generates 3.8-MeV protons, emitted at some angle between the target normal and the laser propagation direction of 45 degrees . Particle-in-cell simulations reveal that the efficient proton acceleration is due to the generation of a quasistatic magnetic field on the target rear side with magnetic pressure inducing and sustaining a charge separation electrostatic field.

Relativistic laser channeling in plasmas for fast ignition

We report an experimental observation suggesting plasma channel formation by focusing a relativistic laser pulse into a long-scale-length preformed plasma. The channel direction coincides with the laser axis. Laser light transmittance measurement indicates laser channeling into the high-density plasma with relativistic self-focusing. A three-dimensional particle-in-cell simulation reproduces the plasma channel and reveals that the collimated hot-electron beam is generated along the laser axis in the laser channeling. These findings hold the promising possibility of fast heating a dense fuel plasma with a relativistic laser pulse.

Early-onset ataxia with ocular motor apraxia and hypoalbuminemia is caused by mutations in a new HIT superfamily gene

Friedreich ataxia (FRDA), the most common autosomal recessive neurodegenerative disease among Europeans and people of European descent, is characterized by an early onset (usually before the age of 25), progressive ataxia, sensory loss, absence of tendon reflexes and pyramidal weakness of the legs. We have recently identified a unique group of patients whose clinical presentations are characterized by autosomal recessive inheritance, early age of onset, FRDA-like clinical presentations and hypoalbuminemia. Linkage to the FRDA locus, however, was excluded. Given the similarities of the clinical presentations to those of the recently described ataxia with oculomotor apraxia (AOA) linked to chromosome 9p13, we confirmed that the disorder of our patients is also linked to the same locus. We narrowed the candidate region and have identified a new gene encoding a member of the histidine triad (HIT) superfamily as the 'causative' gene. We have called its product aprataxin; the gene symbol is APTX. Although many HIT proteins have been identified, aprataxin is the first to be linked to a distinct phenotype.

Comparative studies of the persistence of animal mycoplasmas under different environmental conditions

A comparison of the persistence of mycoplasmas in animals was carried out. When inoculated into liquid media, strains of Mycoplasma bovis, M. arginini, Acholeplasma laidlawii, and A. axanthum persisted for 59-185 days post-inoculation. The survival periods were not significantly influenced by temperature (4, 30, 37 degrees C, and room temperature). The survival periods for M. bovigenitalium, M. gallisepticum, M. bovirhinis, and M. gateae ranged from <7 to 185 days depending on medium components and temperature. Further, it was determined that strains of M. bovigenitalium, M. bovis, M. bovirhinis, M. arginini, and A. laidlawii persisted in a dry paper disc for at most 28, 126, 154, 56 and over >168 days at 4 degrees C, respectively. At 4 degrees C, strains of M. gallisepticum, M. columborale, M. edwardii, M. felis, and M. gateae survived for at most 28, 21, 42, 28, 28 and 70 days, respectively. At 30 degrees C, strains of M. bovis, M. bovirhinis, M. arginini, A. laidlawii, and M. gallisepticum persisted for at most 28, 84, 56, >168 and 14 days, respectively, but strains of M. gallisepticum, M. columborale, M. edwardii, M. felis, M. gateae, and U. diversum did not survive for more than 14 days. In an outdoor environment, strains of M. bovirhinis and A. laidlawii survived for at most 28 and 14 days, respectively. Finally, it was found that 14 isolates of M. gallisepticum persisted for periods similar to those of the reference strains. The results under dry conditions at a variety of temperatures presented contribute to understanding the epizootiology of mycoplasmal infections in the field.

[Use of expectorated sputum to assess airway inflammation of smoking and its cessation]

To investigate the usefulness of expectorated sputum in the assessment of airway inflammation by smoking. I examined cytokine expression in the sputum of healthy smokers and non-smokers, and compared them before, and at 8,12 and 16 weeks after, cessation of smoking. Four cytokines, interleukin (IL) 8, interferon (IFN)-gamma, tumor necrosis factor (TNF)-alpha, and IL-10, were assessed by immunohistochemistry. In smokers, the percentage of bronchial epithelial (BE) cells and macrophages with high intracellular contents of the pro-inflammatory cytokines IL-8, IFN-gamma and TNF-alpha, were significantly increased in comparison with non-smokers. In contrast, expression of IL-10 was significantly decreased in smokers. After smoking cessation, expression of IL-8 was significantly decreased by the 16th week, that of IFN-gamma was significantly decreased by the 12th to the 16th week, but that of TNF-alpha was unchanged even at 16 weeks post-cessation, and that of IL-10 was significantly increased at that time. Cytokine expression in BE cells was similar to that in macrophages. From the data, we concluded that expectorated sputum is useful for assessing airway inflammation due to smoking and for following the series of changes that follow smoking cessation.

Effect of bicozamycin on the eradication of Shiga toxin-producing Escherichia coli in calves

Fifty-nine calves, aged 11 days to 9 months, from three farms breeding Japanese Black beef cattle in Miyazaki Prefecture, Japan, were examined for the presence of Shiga toxin-producing Escherichia coli (STEC). A high prevalence of STEC was detected among calves, with 45 (76.3%) animals carrying STEC including different serogroups (O26, O74, O111, O114, O119, O127, O153, O157, and ONT) and toxin types. The number of STEC in the feces was estimated by a combined method involving enumeration of colony-forming units by a plate-most-probable-number (plate-MPN) technique and polymerase chain reaction for the detection of Shiga toxin genes. Fecal shedding ranged from 10(1) to 10(10) MPN/g feces. To evaluate the safety and efficacy of bicozamycin (BCM: previously named as bicyclomycin) in eradicating STEC, 30 calves carrying STEC with or without diarrhea were examined. Fifteen calves were treated orally with BCM (10 mg/kg/day) once daily for 5 days, and the other 15 were untreated. Twenty-four hours after the last dose, fecal specimens were collected from both groups to compare the number of coliforms and STEC with those before treatment. BCM-treated animals had a significantly lower number of coliforms and STEC compared to the untreated calves. The STEC eradication rate was 86.6% (13/15) in the BCM-treated group, compared to 0% (0/15) in the control group. The corresponding cure rates for diarrhea were 87.5 (7/8) and 0% (0/3), respectively. No adverse reactions were observed in the calves during treatment. It is concluded that BCM is an effective agent for the eradication of STEC in calves with or without diarrhea.

Asymmetrical temporal lobe atrophy with massive neuronal inclusions in multiple system atrophy

This report concerns a rare association of asymmetrical temporal lobe atrophy with multiple system atrophy (MSA). A 53-year-old Japanese woman developed cerebellar ataxia and parkinsonism and was diagnosed as olivopontocerebellar atrophy (OPCA). This patient showed forgetfulness and subsequent disorientation even in the early stage of the disease. She fell into a decorticate state at the age of 64, and died a year later. The autopsy showed MSA with asymmetrical atrophy of temporal lobes, intraneuronal globular inclusions mostly confined to the hippocampus, amygdaloid nucleus, and most abundant in the granule cells in the dentate fascia. These inclusions were intensely argyrophilic and expressed marked immunoreactivity to ubiquitin, but not to neurofilament (NF), tau and paired helical filaments (PHF). Ultrastructurally, they were composed of scattered short filamentous structures of 15 to 30 nm in diameter, ribosome-like granules, mitochondria and lipofuscin. The lack of immunoreactivity against tau, NF and PHF suggests that the inclusions are distinct from Pick bodies. To our knowledge, MSA in association with asymmetrical temporal lobe atrophy with the present neuronal inclusions has not been reported. This case is distinct from MSA combined with atypical Pick's disease in the distribution and immunohistochemical properties of neuronal inclusions, and may present a new variant of MSA since the neuronal inclusions are similar, in many respects, to those of neuronal inclusions reported in MSA. Globular inclusions are also discussed in variants of Pick's disease, amyotrophic lateral sclerosis and Alzheimer's disease.

Characterization of a lentogenic Newcastle disease virus isolated from broiler chickens in Japan

Newcastle disease virus (NDV), named MET95, was isolated from a non-vaccinated broiler flock in Japan in 1995. The MET95 strain was determined to be a lentogenic NDV. The strain has the properties of eluting rapidly at 4 C and has low thermostability in hemagglutinating activity with chicken erythrocytes. In these studies, no difference could be found between the MET95 strain and the Hitcher B1 vaccine strain. However, the chickens inoculated with the MET95 strain, as well as chickens that they were in contact with, had a much higher hemagglutination-inhibition antibody response than those inoculated with the B1 strain. Accordingly, the MET95 strain is thought to be a promising candidate as a live ND vaccine strain. In Japan, this is the first report on the isolation of lentogenic NDV from chickens since the paper on the Ishii strain isolated in 1966.

Feed-out of rear surface perturbation due to rarefaction wave in laser-irradiated targets

We report experimental results on hydrodynamic perturbation transfer from the rear to the front of laser-irradiated targets. Flat polystyrene foils with rear-surface perturbations were irradiated by partially coherent light. We observed phase inversion of the rear surface after the shock breakout at the rear surface. Perturbations on the laser-irradiated surface arose due to the rippled rarefaction wave. Experimental results were well reproduced by a simple model with unperturbed hydrodynamic quantities calculated from the one-dimensional simulation.

[The clinical usefulness of high-dose intravenous immunoglobulin therapy for chronic inflammatory demyelinating polyneuropathy and multifocal motor neuropathy]

To explore the optimum dose of intravenous immunoglobulin (i.v.Ig) for treating patients with chronic inflammatory demyelinating polyrneuropathy and multifocal motor neuropathy, we compared the usefulness of i.v.Ig among 3 treatment doses. Fifty-nine patients were randomly divided into three treatment dosage groups: 20 patients for Group I using 50 mg/kg/day x 5 days, 19 patients Group II using 200 mg/kg/day x 5 days, and 20 patients Group III using 400 mg/kg/day x 5 days. We assessed clinically and electrophysiologically the effectiveness of the treatment at 5 weeks after the initial infusion. For patients in Group I and II who had not improved (or worsened) with the first treatment, we gave a one-step larger dose in the second treatment (i.e. 200 mg/kg/day x 5 days for those who had been given 50 mg/kg/day x 5 days, 400 mg/kg/day x 5 days for those who had been given 200 mg/kg/day x 5 days) after more than 9 weeks. We found that 15% of the patients in Group I, 21% in Group II and 60% in Group III improved dose-dependently with the first intravenous immunoglobulin treatment. Seven (47%) of 16 patients in Group I and 4 (40%) of 11 patients in Group II improved after the second treatment with larger doses. Adverse reactions including chill sensation, fever, skin eruption and increase in blood GOT and GPT levels were transient and mild. One patient in Group III developed left hemiparesis showing the small infarction in the right thalamus during the course of the treatment, but the symptom was mild. In conclusion, the high-dose intravenous immunoglobulin therapy (400 mg/kg/day x 5 days) is useful for treating patients with CIDP and MMN, although care must be taken of the risk of causing cerebral infarctions.

[Extreme decrease of serum total cholesterol and other lipid levels in elderly inpatients]

In this study 112 elderly inpatients (55 men, 57 women) were recruited. 1. Twelve elderly inpatients (5 men, 7 women) aged 82.5 +/- 7.4 years (M +/- SD) were investigated during 3 periods of dietary intake: good intake (period I), tube nutrition (period II) and fasting with intravenous fluid infusion (period III). Calorie, protein, carbohydrate, fat and cholesterol intakes were greater in period I than in periods II and III. Serum total and LDL cholesterols were lowest in period III, when serum HDL cholesterol, triglyceride and total protein were lower in period III than in period I. 2. One hundred elderly inpatients (50 men, 50 women) were divided into 4 groups according to type of decreased serum lipid and a control group. Serum total cholesterol only was decreased in group I, both serum total and HDL cholesterols were decreased in group II, both serum total cholesterol and triglyceride were decreased in group III, all 3 lipids were decreased in group IV and lipid levels did not change in the control group. There were 5 patients in group I, 28 patients in group II, 20 patients in group III, 27 patients in group IV and 20 patients in the control group. The patient's age ranged from 80.3 to 88.4 years and body mass index ranged from 14.7 to 18.4 kg/m2. Serum total protein decreased significantly in groups II-IV, to 5.6 to 5.7 g/dl. Serum total protein, and total cholesterol correlated positively (r = 0.525, p < 0.01), as did Calorie ingestion and serum total cholesterol levels (r = 0.554, p < 0.001). Therefore, severe hypocholesterolemia was accompanied by malnutrition and a decrease in Calorie or cholesterol intake. Serum total cholesterol levels during observation decreased most in group IV, followed by group II similar to serum HDL cholesterol levels. The amount of nutrient intake was smallest in group IV resulting in an extreme lowering of all 3 serum lipid levels.

L-ornithine decarboxylase from Hafnia alvei has a novel L-ornithine oxidase activity

A novel activity producing gamma-aminobutyric acid (GABA) from L-ornithine in the presence of NAD(P)+ was found in the crude extract of L-ornithine-induced Hafnia alvei, in addition to L-ornithine decarboxylase (ODC) activity. The reaction system for the former activity consisted of two enzymes, L-ornithine oxidase (decarboxylating, OOD) and gamma-aminobutyraldehyde (GABL) dehydrogenase (GDH). OOD catalyzed the conversion of L-ornithine into GABL, CO2, NH3, and H2O2 in the presence of O2, and GDH dehydrogenated GABL to GABA in the presence of NAD(P)+. OOD, purified to homogeneity, had a high ODC activity and the activity ratio of ODC to OOD was almost constant throughout the purification (ODC/ OOD=160:1). The molecular mass of the OOD was about 230 kDa, probably consisting of three identical subunits of a 77 kDa peptide, and OOD had an absorption maximum at 420 nm as well as at 278 nm, the specific absorption for an enzyme containing pyridoxal phosphate (PLP). The content of PLP was estimated at about 1 mol per subunit. OOD was specific to L-ornithine, and other L-amino acids and polyamines including putrescine were inert. The enzyme was activated by PLP, but not by pyridoxamine 5'-phosphate, FAD, FMN, or pyrroloquinoline quinone, and it was inactivated by hydrazine, semicarbazide, and hydroxylamine. The holoenzyme can be resolved to the apoenzyme by incubation with hydroxylamine, and reconstituted with PLP. These properties of OOD were almost the same as those of ODC separately purified to homogeneity from H. alvei. Zn2+ and Cu2+, butanedione, and sodium borohydride inhibited both OOD and ODC in a similar manner. The OOD reaction required O2 and only the ODC reaction proceeded under anaerobic conditions. The substitution of air for oxygen in the reaction vessel and the addition of catalase-H2O, enhanced only the OOD reaction, resulting in an increase of the ratio of OOD/ODC to 1:30 and 1:4.1, respectively. These results suggested that OOD and ODC are identical and that the former is a side reaction of the latter in the presence of O2.

A filter immunobinding technique for the rapid detection and simultaneous identification of avian and bovine mycoplasmas

A filter immunobinding (FIB) method was developed for the detection and identification of mycoplasmas. Type strains of a total of 18 avian and bovine mycoplasma species propagated in broth media were diluted and immobilized on a nitrocellulose membrane as antigens for investigating the specificity with rabbit hyperimmune sera. Non-specific FIB reactions were easily eliminated by the procedure of absorbing rabbit hyperimmune sera in the broth. Absorbed rabbit hyperimmune sera exhibited clear species-specificity with mycoplasma antigens by the FIB. These specific reactions always agreed with the results of identification by tests of biochemical properties and growth inhibition for the isolates of M. bovirhinis, M. bovis, M. columbinum, M. columborale, M. gallisepticum and M. synoviae. Some bovine mycoplasma species, which were impossible to identify by growth inhibition test, because of their strong production of film and spots on the agar, specifically reacted with absorbed rabbit hyperimmune sera against M. bovis in the FIB. The detection limit of mycoplasmas by this method was about 10(4)-10(5) colony-forming units/ml, which is lower than that of colony determination on agar. The FIB seems to be a useful technique for rapid detection and simultaneous identification of mycoplasmas.

Features of idiopathic pulmonary fibrosis with organizing pneumonia

To characterize the clinical features of patients with idiopathic pulmonary fibrosis (IPF) having organizing pneumonia (OP), we retrospectively reviewed the clinical charts, chest X-rays, CT scans, and transbronchial lung biopsy (TBLB) specimens of patients with IPF. Patients with IPF and OP had a subacute onset of symptoms (within 2 months) (87.5%), leukocytosis (> 10,000/mm3) (62.5%), and a strong C-reactive protein (CRP) reaction (> 3+) (75%). Some of these features were distinctly different from those of IPF patients without OP (subacute onset of symptoms 0%, leukocytosis 0%, strong CRP reaction 16.7%). In the patients with IPF with OP, A-aDo2 and semiquantitative scores of chest X-ray abnormalities improved significantly after prednisolone treatment. Those abnormalities improved only slightly in the patients with IPF without OP. Diffusing capacity remained decreased and abnormal interstitial infiltration persisted, even after prednisolone treatment in the patients with IPF with or without OP. Clinical features of IPF patients with OP differed from those of patients with IPF without OP. IPF patients with OP showed good clinical response to corticosteroid therapy. These findings warrant further study of the presence of OP in TBLB specimens in predicting corticosteroid responsiveness and prognosis of patients with IPF.

Sex difference in serum 7 alpha-hydroxycholesterol levels in the rat reflect hepatic activity of 3 beta-hydroxy-delta 5-C27-steroid dehydrogenase and cholesterol 7 alpha-hydroxylase

Factors that affect serum levels of 7 alpha-hydroxycholesterol were studied in the rat. Serum levels of 7 alpha-hydroxycholesterol differed in male and female rats fed regular chow (male; 0.2 +/- 0.1 nmol/ml (mean +/- SD); n = 8; female; 0.4 +/- 0.1 nmol/ml; n = 8). When rats were fed with chow to which 3% cholestyramine had been added, the level increased significantly, particularly in female rats (male; 0.6 +/- 0.3 nmol/ml; n = 8; female; 2.4 +/- 1.5 nmol/ml; n = 8). The liver activity of cholesterol 7 alpha-hydroxylase, the rate-limiting enzyme for degradation of cholesterol, did not show any sex differences, irrespective of whether the animals were fed with regular chow (male; 51 +/- 15 pmol/min per mg protein; n = 8; female; 58 +/- 21 pmol/min per mg protein; n = 8), or the cholestyramine-supplemented chow (male; 162 +/- 33 pmol/min per mg protein; n = 8; female; 172 +/- 33 pmol/min per mg protein; n = 8). In contrast, the activity of 3 beta-hydroxy-delta 5-C27-steroid dehydrogenase, which acts after cholesterol 7 alpha-hydroxylase in the catabolism of cholesterol, showed a marked difference between the sexes. In both sexes this enzyme activity was higher in cholestyramine-treated rats (male; 963 +/- 78 pmol/min per mg protein; n = 8; female; 708 +/- 106 pmol/min per mg protein, n = 8) compared to that in that rats received regular chow (male; 622 +/- 83 pmol/min per mg protein; n = 8; female; 469 +/- 41 pmol/min per mg protein; n = 8). If the serum level of 7 alpha-hydroxycholesterol depended solely on the enzyme activity of cholesterol 7 alpha-hydroxylase, it would be difficult to explain these sex differences, since there were no sex differences in levels of cholesterol 7 alpha-hydroxylase. These results clearly indicate that, in the rat, the serum level of 7 alpha-hydroxycholesterol depends not only on cholesterol 7 alpha-hydroxylase activity but also on 3 beta-hydroxy-delta 5-C27-steroid dehydrogenase activity.

Survival of mycoplasmas inoculated in horse sera

Although it is known that commercialized bovine serum is sometimes contaminated with mycoplasmas, it is not clear whether mycoplasmas can survive in horse serum. In this study, as a preliminary examination of the survival of mycoplasmas inoculated in horse sera, the survivability of 8 strains of 7 mycoplasmas was tested. The results obtained reveal that two strains of M. bovis and M. gallisepticum were found to survive in non-heated and inactivated sera for 94 to 330 days at 30 or 37 degrees C. Three strains of M. bovirhinis, M. gateae and A. laidlawii lived for 7 to 330 days depending upon the temperature maintained or pH of the serum. Strains of M. bovigenitalium and U. diversum survived for a maximum of 8 days in all horse sera tested. Therefore, mycoplasmas are generally likely to survive for a long period in horse serum although the survival period depends on the species, strain and temperature.

Isolation of mycoplasmas from fantail pigeons

Isolation of mycoplasmas from the oropharynxes of 60 fantails reared under natural conditions at different zoological parks in Miyazaki prefecture was carried out. Mycoplasma columbinum, M. columborale and M. columbinasale were isolated from 28 (46.7%), 22 (36.7%), and 1 (1.7%) of 60 oropharynxes, respectively, but no Mycoplasma was isolated from 5 cloacas tested. Ureaplasma was not isolated from any of the 28 oropharynxes or 5 cloacas examined. We report that 41 (68.3%) of 60 fantails had one or two species of mycoplasmas in their oropharynxes, and make the first confirmation of M. columbinasale inhabiting a Japanese pigeon.

Temperature- and pH-dependent cytotoxic effect of the hemolytic lectin CEL-III from the marine invertebrate Cucumaria echinata on various cell lines

We investigated the cytotoxicity of CEL-III, one of four Ca2+-dependent galactose/N-acetylgalactosamine (GalNAc)-binding lectins from the marine invertebrate Cucumaria echinata. Among six cell lines tested, MDCK cells showed the highest susceptibility to CEL-III cytotoxicity and its LD50 was estimated to be 53 ng/ml, while no significant cytotoxicity of CEL-III was observed in CHO cells up to 10,000 ng/ml. In the presence of 0.1 M lactose, the cytotoxicity of CEL-III was strongly inhibited. The binding studies using FITC-labeled CEL-III revealed that the amount of CEL-III bound to MDCK cells was about 2-fold greater than that in the case of CHO cells. The cytotoxicity of CEL-III increased with decreasing temperature. The surviving fractions of Vero cells exposed to CEL-III at 4 degrees C were immediately decreased, and more than 90% of exposed cells were killed within 20 min, whereas at 37 degrees C much longer exposure period (more than 10 h) was required to kill 50% of the cells. CEL-III induced the release of carboxyfluorescein (CF) from CF-loaded MDCK cells and this activity was markedly increased at alkaline pH (pH 10) and at lower temperature (4 degrees C). Even in CHO cells, considerable CF release was induced by CEL-III at 4 degrees C and at pH 10 but not at pH 7.5 at both temperatures. In agreement with these results, CHO cells exposed to CEL-III at 4 degrees C and at pH 10 were killed in a dose-dependent manner. These results suggest that CEL-III exhibits cytotoxicity through damaging the plasma membrane by pore-formation in a temperature- and pH-dependent manner. Different susceptibility of each cell line to CEL-III cytotoxicity may be due to differences in the processes leading to pore-formation after binding to cell-surface carbohydrates.

Carbohydrate-binding properties of the hemolytic lectin CEL-III from the holothuroidea Cucumaria echinata as analyzed using carbohydrate-coated microplate

The carbohydrate-binding properties of the hemolytic lectin CEL-III from the Holothuroidea Cucumaria echinata were studied using the microplate assay system which we have recently developed [Hatakeyama et al. (1996) Anal. Biochem. 237, 188-192]. When the binding of CEL-III to lactose covalently immobilized on a microplate was examined using colloidal gold solution, the binding was detected with as little as 1 microgram/ml protein. Affinity of several carbohydrates to CEL-III was assessed by means of an inhibition experiment using the lactose-coated plate and it was found that N-acetylgalactosamine has the highest affinity for CEL-III, followed by lactose and lactulose. Examination of the binding of CEL-III to the lactose-coated plate at various pH values and temperatures revealed that the affinity is higher in the acidic pH region and at lower temperatures. From the Ca(2+)-dependence profile for the binding of CEL-III to the lactose-coated plate, the apparent dissociation constant for Ca2+ was estimated to be 2.3 mM. These results suggested that the carbohydrate-binding properties of CEL-III are closely related to its hemolytic activity, although an additional interaction between the protein and the lipid bilayer, which is enhanced in the alkaline pH region, also seems to be necessary for its hemolytic action.

Quantitative comparison between serum components and somatic cells in bovine quarter milk

Quantitative comparisons between serum components and somatic cells in 202 bovine quarter milks collected at 3 dairy farms were conducted. Detection of serum components was carried out by an immunological technique, and cell counts were calculated by Breed's method. A high correlation (r = 0.77) between cell counts and gamma-globulin contents was demonstrated, while correlation between cell counts and serum albumin was not close (r = 0.45). In a comparison between cell counts and gamma-globulin contents, 19 (65.4%) out of 29 milks containing over 500,000 cells/ml had gamma-globulin less than 1.138 mg/ml, which was also seen in 97% of 172 milks having less than 500,000 cells/ml. From these results, it was suggested that the gamma-globulin content of milk might be of use for differentiating normal milk from abnormal ones.

Antibody response to Mycoplasma bovis of calves introduced to a farm contaminated with the organism

Antibody against Mycoplasma bovis in sera of 48 calves introduced to a farm, in which calf pneumonia associated with M. bovis had been occurring in the last 3 years, was detected by an indirect hemagglutination test. Significant rises of antibody titers in sera of calves belonging to the groups A (16 calves) and B (14 calves) were recorded by day 60 post-introduction. On the other hand, a significant increase of antibody titers of 18 calves in group C, which had been administered antibiotics as a preventive therapy, was demonstrated at day 248 after arrival. These results indicated that the spread of M. bovis infection occurred easily on the contaminated farm, and a preventive therapy could delay the outbreak of calf pneumonia associated with M. bovis.

Oligomerization of the hemolytic lectin CEL-III from the marine invertebrate Cucumaria echinata induced by the binding of carbohydrate ligands

The hemolytic lectin CEL-III is a Ca2+-dependent, galactose/GalNAc-specific lectin purified from the marine invertebrate Cucumaria echinata (Holothuroidea). We found that this lectin forms ion-permeable pores in erythrocyte and artificial lipid membranes that have specific carbohydrate ligands on the surface. The hemolytic activity of CEL-III exhibited characteristic pH dependence; activity increased remarkably with pH in the alkaline region, especially above pH 9. When rabbit erythrocyte membrane was examined by immunoblotting using anti-CEL-III antiserum after treatment with CEL-III, the irreversible binding of the CEL-III oligomer increased with pH, indicating that the increase in hemolytic activity at higher pH is associated closely with the amount of oligomer irreversibly bound to the membrane. Surface hydrophobicity of CEL-III, as measured by the fluorescent probe 8-anilino-1-naphthalenesulfonate, increased markedly with the binding of specific ligands such as lactose, lactulose, and N-acetyllactosamine at pH 9-10 in the presence of 1 M NaCl. The enhancement of surface hydrophobicity induced by the binding of carbohydrates was also accompanied by the formation of a CEL-III oligomer, which was found to be the same size on sodium dodecyl sulfate-polyacrylamide gel electrophoresis as the oligomer that formed in CEL-III-treated erythrocyte membranes. Far-UV circular dichroism spectra of CEL-III and the oligomer revealed a definite difference in secondary structure. These data suggest that the binding of CEL-III to specific carbohydrate ligands on the erythrocyte surface induces a conformational change in the protein, leading to the exposure of a hydrophobic region which triggers oligomerization and the irreversible binding of the protein to the membrane.