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1.
Opt Express ; 31(15): 24045-24053, 2023 Jul 17.
Article in English | MEDLINE | ID: mdl-37475241

ABSTRACT

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.

2.
Nat Commun ; 10(1): 5614, 2019 12 09.
Article in English | MEDLINE | ID: mdl-31819056

ABSTRACT

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.

3.
Rev Sci Instrum ; 88(7): 075103, 2017 Jul.
Article in English | MEDLINE | ID: mdl-28764534

ABSTRACT

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.

4.
Sci Rep ; 7: 42451, 2017 02 13.
Article in English | MEDLINE | ID: mdl-28211913

ABSTRACT

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.

5.
Phys Rev E Stat Nonlin Soft Matter Phys ; 81(3 Pt 2): 036410, 2010 Mar.
Article in English | MEDLINE | ID: mdl-20365885

ABSTRACT

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.

6.
Phys Rev Lett ; 102(23): 235002, 2009 Jun 12.
Article in English | MEDLINE | ID: mdl-19658942

ABSTRACT

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.

7.
Phys Rev E Stat Nonlin Soft Matter Phys ; 77(1 Pt 2): 016401, 2008 Jan.
Article in English | MEDLINE | ID: mdl-18351938

ABSTRACT

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.

8.
Phys Rev E Stat Nonlin Soft Matter Phys ; 76(6 Pt 2): 066403, 2007 Dec.
Article in English | MEDLINE | ID: mdl-18233928

ABSTRACT

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.

9.
Nihon Kokyuki Gakkai Zasshi ; 39(7): 461-5, 2001 Jul.
Article in Japanese | MEDLINE | ID: mdl-11579523

ABSTRACT

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.


Subject(s)
Cytokines/analysis , Inflammation Mediators/analysis , Respiratory Tract Diseases/diagnosis , Respiratory Tract Diseases/etiology , Smoking/adverse effects , Sputum/metabolism , Adult , Aged , Biomarkers/analysis , Bronchi/cytology , Epithelial Cells/metabolism , Female , Humans , Inflammation/diagnosis , Inflammation/etiology , Macrophages, Alveolar/metabolism , Male , Middle Aged , Smoking Cessation , Sputum/cytology , Time Factors
10.
Nat Genet ; 29(2): 184-8, 2001 Oct.
Article in English | MEDLINE | ID: mdl-11586299

ABSTRACT

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.


Subject(s)
Apraxias/genetics , Ataxia/genetics , DNA-Binding Proteins/genetics , Mutation , Nuclear Proteins/genetics , Oculomotor Muscles/physiopathology , Serum Albumin/metabolism , Amino Acid Sequence , Animals , Apraxias/complications , Ataxia/complications , Chromosome Mapping , Chromosomes, Human, Pair 9 , DNA-Binding Proteins/chemistry , Female , Genetic Linkage , Humans , Male , Molecular Sequence Data , Nuclear Proteins/chemistry , Pedigree , Phylogeny , Sequence Homology, Amino Acid
11.
Vet Microbiol ; 82(3): 223-32, 2001 Sep 28.
Article in English | MEDLINE | ID: mdl-11470544

ABSTRACT

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.


Subject(s)
Mycoplasma/growth & development , Animals , Culture Media , Mycoplasma/physiology , Mycoplasma Infections/microbiology , Mycoplasma Infections/veterinary , Temperature , Time Factors , Water
12.
J Neurol Sci ; 179(S 1-2): 50-8, 2000 Oct 01.
Article in English | MEDLINE | ID: mdl-11054485

ABSTRACT

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.


Subject(s)
Atrophy/etiology , Atrophy/pathology , Functional Laterality/physiology , Inclusion Bodies/pathology , Multiple System Atrophy/complications , Multiple System Atrophy/pathology , Nerve Degeneration/pathology , Neurons/pathology , Temporal Lobe/pathology , Atrophy/diagnostic imaging , Disease Progression , Female , Humans , Inclusion Bodies/metabolism , Middle Aged , Multiple System Atrophy/diagnostic imaging , Nerve Degeneration/metabolism , Neurons/metabolism , Radiography , Temporal Lobe/diagnostic imaging
13.
Phys Rev Lett ; 84(23): 5331-4, 2000 Jun 05.
Article in English | MEDLINE | ID: mdl-10990936

ABSTRACT

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.

14.
Avian Dis ; 44(3): 686-90, 2000.
Article in English | MEDLINE | ID: mdl-11007020

ABSTRACT

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.


Subject(s)
Chickens/virology , Newcastle disease virus/classification , Animals , Erythrocytes/virology , Hemagglutination Tests , Japan , Newcastle disease virus/immunology , Newcastle disease virus/pathogenicity , Vaccines, Attenuated , Viral Vaccines
15.
Microbiol Immunol ; 44(11): 891-6, 2000.
Article in English | MEDLINE | ID: mdl-11145269

ABSTRACT

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.


Subject(s)
Anti-Bacterial Agents/therapeutic use , Bridged Bicyclo Compounds, Heterocyclic/therapeutic use , Cattle Diseases/drug therapy , Escherichia coli Infections/veterinary , Escherichia coli/drug effects , Shiga Toxins/biosynthesis , Animals , Cattle , Cattle Diseases/epidemiology , Cattle Diseases/microbiology , Colony Count, Microbial , Escherichia coli/isolation & purification , Escherichia coli/metabolism , Escherichia coli Infections/drug therapy , Escherichia coli Infections/epidemiology , Escherichia coli Infections/microbiology , Feces/microbiology , Prevalence
16.
Biosci Biotechnol Biochem ; 63(7): 1279-84, 1999 Jul.
Article in English | MEDLINE | ID: mdl-10478454

ABSTRACT

The pore-forming activity of CEL-III, a Gal/GalNAc specific lectin from the Holothuroidea Cucumaria echinata, was examined using artificial lipid membranes as a model system of erythrocyte membrane. The carboxyfluorescein (CF)-leakage studies clearly indicated that CEL-III induced the formation of pores in the dipalmitoyl phosphatidyl choline (DPPC)-lactosyl ceramide (LacCer) liposomes effectively but not in the DPPC-glucosyl ceramide (GlcCer) liposomes or DPPC liposomes. Such a leakage of CF was strongly inhibited by lactose, a potent inhibitor of CEL-III, suggesting that the leakage is mediated through the specific binding of CEL-III to the carbohydrate chains on the surface of the liposomes. The leakage of CF from the DPPC-lactosyl ceramide liposomes was pH-dependent, and it increased with increasing pH. The immunoblotting analysis and circular dichroism data indicated that upon interaction with liposomes, CEL-III associated to form an oligomer concomitantly with a marked conformational change. Furthermore, channel measurements showed that CEL-III has an ability to form small ion channels in the planar lipid bilayers consisting of diphytanoylphosphatidylcholine and human globoside (Gb4Cer)/LacCer.


Subject(s)
Lectins/chemistry , Lipid Bilayers/chemistry , Sea Cucumbers/chemistry , Animals , Blotting, Southern , Circular Dichroism , Fluoresceins/chemistry , Hemolysis , Humans , Hydrogen-Ion Concentration , Liposomes , Molecular Weight , Patch-Clamp Techniques , Porosity
17.
No To Shinkei ; 51(2): 127-35, 1999 Feb.
Article in Japanese | MEDLINE | ID: mdl-10198901

ABSTRACT

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.


Subject(s)
Demyelinating Diseases/therapy , Immunoglobulins, Intravenous/administration & dosage , Motor Neuron Disease/therapy , Peripheral Nervous System Diseases/therapy , Polyneuropathies/therapy , Adolescent , Adult , Aged , Chronic Disease , Demyelinating Diseases/physiopathology , Drug Administration Schedule , Drug Evaluation , Electrophysiology , Humans , Middle Aged , Motor Neuron Disease/physiopathology , Neural Conduction , Peripheral Nervous System Diseases/physiopathology , Polyneuropathies/physiopathology
18.
Nihon Ronen Igakkai Zasshi ; 35(5): 389-95, 1998 May.
Article in Japanese | MEDLINE | ID: mdl-9711094

ABSTRACT

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.


Subject(s)
Cholesterol/blood , Diet , Lipids/blood , Nutritional Status , Aged , Aged, 80 and over , Blood Proteins/analysis , Body Mass Index , Female , Humans , Inpatients , Male
19.
J Vet Med Sci ; 59(11): 965-9, 1997 Nov.
Article in English | MEDLINE | ID: mdl-9409509

ABSTRACT

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.


Subject(s)
Cattle Diseases , Mycoplasma Infections/veterinary , Mycoplasma/classification , Mycoplasma/isolation & purification , Poultry Diseases , Animals , Antigens, Bacterial/analysis , Cattle , Chickens , Immune Sera , Immunoassay/methods , Microbial Sensitivity Tests , Mycoplasma Infections/diagnosis , Rabbits , Species Specificity
20.
J Gastroenterol ; 32(4): 502-6, 1997 Aug.
Article in English | MEDLINE | ID: mdl-9250898

ABSTRACT

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.


Subject(s)
3-Hydroxysteroid Dehydrogenases/metabolism , Cholesterol 7-alpha-Hydroxylase/metabolism , Hydroxycholesterols/blood , Liver/enzymology , Animals , Cholestyramine Resin/pharmacology , Female , Male , Rats , Rats, Wistar , Sex Characteristics
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