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1.
Opt Express ; 31(15): 24045-24053, 2023 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-37475241

RESUMO

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 Genet ; 29(2): 184-8, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11586299

RESUMO

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.


Assuntos
Apraxias/genética , Ataxia/genética , Proteínas de Ligação a DNA/genética , Mutação , Proteínas Nucleares/genética , Músculos Oculomotores/fisiopatologia , Albumina Sérica/metabolismo , Sequência de Aminoácidos , Animais , Apraxias/complicações , Ataxia/complicações , Mapeamento Cromossômico , Cromossomos Humanos Par 9 , Proteínas de Ligação a DNA/química , Feminino , Ligação Genética , Humanos , Masculino , Dados de Sequência Molecular , Proteínas Nucleares/química , Linhagem , Filogenia , Homologia de Sequência de Aminoácidos
3.
Nat Commun ; 10(1): 5614, 2019 12 09.
Artigo em Inglês | MEDLINE | ID: mdl-31819056

RESUMO

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.

4.
Phys Rev E Stat Nonlin Soft Matter Phys ; 77(1 Pt 2): 016401, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18351938

RESUMO

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.

5.
Phys Rev E Stat Nonlin Soft Matter Phys ; 76(6 Pt 2): 066403, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18233928

RESUMO

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.

6.
Rev Sci Instrum ; 88(7): 075103, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28764534

RESUMO

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.

7.
Sci Rep ; 7: 42451, 2017 02 13.
Artigo em Inglês | MEDLINE | ID: mdl-28211913

RESUMO

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.

8.
Phys Rev Lett ; 84(23): 5331-4, 2000 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-10990936

RESUMO

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.

9.
J Biochem ; 116(1): 209-14, 1994 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-7798179

RESUMO

Four Ca(2+)-dependent, N-acetylgalactosamine/galactose-specific lectins were purified from the marine invertebrate, Cucumaria echinata (Holothuroidea), by column chromatography on lactosyl-Sepharose 4B, Sephacryl S-200, and Q-Sepharose. The molecular masses of these lectins were estimated to be 27 kDa (CEL-I), 35 kDa (CEL-II), 45 kDa (CEL-III), and 68 kDa (CEL-IV) on SDS-PAGE under nonreducing conditions. Among these lectins, CEL-I and CEL-IV strongly agglutinated rabbit and human erythrocytes, and were found to recognize N-acetylgalactosamine and galactose-containing carbohydrates from the results of a hemagglutination inhibition assay. In contrast, CEL-II failed to agglutinate any erythrocytes tested, although its carbohydrate-binding ability was confirmed by a carbohydrate-binding assay involving asialofetuin-horseradish peroxidase. Interestingly, CEL-III caused hemolysis of rabbit and human erythrocytes, while it showed only hemagglutination of chicken and horse erythrocytes at relatively high concentrations. The hemolytic activity of CEL-III was also dependent on the Ca(2+)-concentration, and inhibited by N-acetylgalactosamine and galactose-containing carbohydrates, suggesting that the hemolysis was caused by Ca(2+)-dependent binding of CEL-III to specific carbohydrate chains on the erythrocyte surface and the following partial destruction of the membrane.


Assuntos
Cálcio/farmacologia , Lectinas/isolamento & purificação , Pepinos-do-Mar/química , Animais , Carboidratos/farmacologia , Eritrócitos/metabolismo , Testes de Hemaglutinação , Humanos , Peso Molecular
10.
J Biochem ; 121(1): 63-7, 1997 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9058193

RESUMO

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.


Assuntos
Bioquímica/métodos , Metabolismo dos Carboidratos , Lectinas/metabolismo , Pepinos-do-Mar/química , Animais , Bioquímica/instrumentação , Cálcio/metabolismo , Sequência de Carboidratos , Carboidratos/química , Coloide de Ouro , Concentração de Íons de Hidrogênio , Lactose/química , Lactose/metabolismo , Lectinas/química , Dados de Sequência Molecular , Temperatura
11.
J Biochem ; 121(3): 560-7, 1997 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9133626

RESUMO

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.


Assuntos
Lectinas/farmacologia , Toxinas Marinhas/farmacologia , Animais , Linhagem Celular , Membrana Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Hemólise/efeitos dos fármacos , Humanos , Concentração de Íons de Hidrogênio , Lectinas/isolamento & purificação , Lectinas/metabolismo , Toxinas Marinhas/isolamento & purificação , Toxinas Marinhas/metabolismo , Ligação Proteica , Temperatura
12.
J Biochem ; 122(5): 961-8, 1997 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9443811

RESUMO

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.


Assuntos
Enterobacteriaceae/enzimologia , Ornitina Descarboxilase/metabolismo , Ornitina/metabolismo , Oxirredutases/metabolismo , Aldeído Oxirredutases/isolamento & purificação , Aldeídos/metabolismo , Sequência de Aminoácidos , Enterobacteriaceae/crescimento & desenvolvimento , Dados de Sequência Molecular , Ornitina Descarboxilase/química , Ornitina Descarboxilase/isolamento & purificação , Oxigênio/metabolismo , Ácido gama-Aminobutírico/metabolismo
13.
J Neurol Sci ; 109(1): 102-6, 1992 May.
Artigo em Inglês | MEDLINE | ID: mdl-1517758

RESUMO

An immunohistochemical study focusing on glial cells was performed using monoclonal antibodies against microtubule-associated proteins (MAP1, MAP2 and MAP5), transferrin, leukocyte common antigen (LCA) and glial fibrillary acidic protein (GFAP) in 5 cases of multiple system atrophy (MSA) exhibiting olivopontocerebellar atrophy and striatonigral degeneration. An antibody to MAP5, a fetal antigen in developing brain, was strongly demonstrated in the glial cytoplasmic inclusions (GCIs) which have recently drawn a great deal of attention and were observed in all 5 cases of MSA. Moreover, MAP5-positive glial cells (MAP5-Gs) were present in significantly higher number than in the controls in various regions where GCIs were found, predominantly in putamen, substantia nigra, cerebellar white matter and internal capsule. LCA and transferrin, markers of microglia and oligodendroglia, respectively, were immunohistochemically detected in some MAP5-Gs. GFAP, on the other hand, was not expressed in MAP5-Gs at all. These findings suggest that MAP5-Gs consist of reactive microglia and oligodendroglia. Our study is the first to demonstrate immunohistochemical detection of MAP5 in glial pathological changes in MSA.


Assuntos
Química Encefálica , Macrófagos/metabolismo , Proteínas Associadas aos Microtúbulos/biossíntese , Proteínas do Tecido Nervoso/biossíntese , Oligodendroglia/metabolismo , Atrofias Olivopontocerebelares/metabolismo , Idoso , Atrofia , Biomarcadores , Corpo Estriado/química , Corpo Estriado/patologia , Feminino , Expressão Gênica , Humanos , Macrófagos/patologia , Masculino , Pessoa de Meia-Idade , Neoplasias/metabolismo , Degeneração Neural , Oligodendroglia/patologia , Atrofias Olivopontocerebelares/patologia , Pneumonia/metabolismo , Síndrome de Shy-Drager/metabolismo , Síndrome de Shy-Drager/patologia , Substância Negra/química , Substância Negra/patologia , Transferrina/análise
14.
J Neurol Sci ; 179(S 1-2): 50-8, 2000 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-11054485

RESUMO

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.


Assuntos
Atrofia/etiologia , Atrofia/patologia , Lateralidade Funcional/fisiologia , Corpos de Inclusão/patologia , Atrofia de Múltiplos Sistemas/complicações , Atrofia de Múltiplos Sistemas/patologia , Degeneração Neural/patologia , Neurônios/patologia , Lobo Temporal/patologia , Atrofia/diagnóstico por imagem , Progressão da Doença , Feminino , Humanos , Corpos de Inclusão/metabolismo , Pessoa de Meia-Idade , Atrofia de Múltiplos Sistemas/diagnóstico por imagem , Degeneração Neural/metabolismo , Neurônios/metabolismo , Radiografia , Lobo Temporal/diagnóstico por imagem
15.
J Neurol Sci ; 114(2): 205-8, 1993 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-8445402

RESUMO

Two MELAS (mitochondrial myopathy, encephalopathy, lactic acidosis and stroke-like episodes) patients with diabetes mellitus (DM), and their family members are described clinically and genetically. The probands have the following features in common; normal early development, short stature, deterioration of intellectual ability, convulsions, cardiac conduction defect, sensorineural hearing loss, cortical blindness, and hemiparesis. Biochemical tests showed high levels of lactate and pyruvate in the blood and cerebrospinal fluid. Muscle biopsy showed ragged-red fibers. Molecular genetic analysis of both patients revealed that they had an A-to-G substitution at nucleotide position 3243 of the mitochondrial DNA in a heteroplasmic fashion. From these clinical and molecular genetic data they were diagnosed as having MELAS. In addition, fasting blood glucose levels were also high and they were diagnosed as having insulin-dependent DM. Some of the maternal family members in both cases also had insulin-dependent DM and several clinical symptoms of MELAS. DM and clinical features of MELAS were transmitted exclusively in the maternal line. In these cases, DM and MELAS might be a clinical manifestation of the same metabolic defect.


Assuntos
DNA Mitocondrial/genética , Diabetes Mellitus Tipo 1/genética , Síndrome MELAS/genética , Mutação , Adolescente , Adulto , Sequência de Bases , Biópsia , Southern Blotting , DNA Mitocondrial/sangue , DNA Mitocondrial/isolamento & purificação , Diabetes Mellitus Tipo 1/complicações , Diabetes Mellitus Tipo 1/fisiopatologia , Feminino , Variação Genética , Humanos , Síndrome MELAS/complicações , Síndrome MELAS/fisiopatologia , Masculino , Pessoa de Meia-Idade , Músculos/patologia , Linhagem , Fenótipo , RNA de Transferência de Leucina/genética , Mapeamento por Restrição
16.
J Neurol Sci ; 138(1-2): 66-77, 1996 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8791241

RESUMO

A 57-year-old man had exhibited cortical sensory disturbance, rigidity, spasticity, dementia, alien hand, grasp reflex, supranuclear ophthalmoplegia, pseudobulbar palsy, and neck dystonia for 4 years. Histological examination of autopsied specimens revealed neuronal loss in the cerebral cortex, with ballooned neurons, subthalamic nucleus, substantia nigra, basal ganglia, midbrain tegmentum, and the thalamus. There were neurofibrillary tangles in the subthalamic nucleus and the substantia nigra. Gallyas-Braak silver impregnation demonstrated numerous argentophilic tangles, threads, and a few argentophilic glia in the cerebral cortex, subcortical white matter, particularly in the precentral gyrus, subcortical nuclei, and the brainstem. These argentophilic structures were largely positive for tau, and negative for ubiquitin, paired helical filaments, and phosphorylated neurofilament. Ultrastructurally, 15-nm-wide straight tubules were observed in the neurons of the substantia nigra, globus pallidus, and the precentral cortex, coexisting with a few twisted tubules periodically constricted at 160- to 230-nm intervals. It was conclusively shown that Gallyas- and tau-positive cytoskeletal abnormalities occurred widely in brain of corticobasal degeneration. Both distribution and morphology of abnormal phosphorylated tau protein in corticobasal degeneration appear to resemble these features in progressive supranuclear palsy. These findings suggest a common cytoskeletal etiopathological significance in corticobasal degeneration and progressive supranuclear palsy.


Assuntos
Gânglios da Base/fisiopatologia , Córtex Cerebral/fisiopatologia , Citoesqueleto/ultraestrutura , Degeneração Neural/fisiologia , Emaranhados Neurofibrilares/patologia , Paralisia Supranuclear Progressiva/patologia , Gânglios da Base/patologia , Córtex Cerebral/patologia , Lateralidade Funcional/fisiologia , Humanos , Imuno-Histoquímica , Masculino , Microscopia Eletrônica , Pessoa de Meia-Idade , Neuroglia/patologia , Coloração pela Prata
17.
J Gastroenterol ; 32(4): 502-6, 1997 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9250898

RESUMO

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.


Assuntos
3-Hidroxiesteroide Desidrogenases/metabolismo , Colesterol 7-alfa-Hidroxilase/metabolismo , Hidroxicolesteróis/sangue , Fígado/enzimologia , Animais , Resina de Colestiramina/farmacologia , Feminino , Masculino , Ratos , Ratos Wistar , Caracteres Sexuais
18.
J Gastroenterol ; 31(3): 441-5, 1996 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8726839

RESUMO

A 21-year-old man was referred to our hospital because of a liver mass lesion detected by abdominal ultrasonography. He had received no hormonal treatment. Physical examinations revealed no abnormalities, and laboratory data, including hepatic function test results, were within normal ranges, with the exception of elevated levels of serum protein induced by vitamin K absence or antagonist (PIVKA)-II (2.2 AU/ml). Abdominal ultrasonography revealed a hyperechoic mass lesion measuring 10 x 10 cm, with hypoechoic areas located in the right posterior segment of the liver. A low-density area and a hypervascular area were detected in the right posterior segment of the liver by computed tomography and celiac angiography, respectively. As hepatocellular carcinoma could not be completely excluded, the tumor was resected. The tissue consisted of sheets of tumor cells with eosinophilic cytoplasm and round nuclei showing a thin trabecular pattern, and these histological findings indicated liver cell adenoma. After resection of the tumor, serum PIVKA-II returned to the normal level.


Assuntos
Adenoma de Células Hepáticas/diagnóstico , Biomarcadores Tumorais/sangue , Biomarcadores , Neoplasias Hepáticas/diagnóstico , Precursores de Proteínas/análise , Protrombina/análise , Adenoma de Células Hepáticas/cirurgia , Adulto , Biópsia por Agulha , Carcinoma Hepatocelular/diagnóstico , Diagnóstico Diferencial , Diagnóstico por Imagem , Hepatectomia , Humanos , Fígado/patologia , Neoplasias Hepáticas/cirurgia , Masculino
19.
Vet Microbiol ; 82(3): 223-32, 2001 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-11470544

RESUMO

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.


Assuntos
Mycoplasma/crescimento & desenvolvimento , Animais , Meios de Cultura , Mycoplasma/fisiologia , Infecções por Mycoplasma/microbiologia , Infecções por Mycoplasma/veterinária , Temperatura , Fatores de Tempo , Água
20.
J Antibiot (Tokyo) ; 31(6): 593-7, 1978 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-681241

RESUMO

A single dose of 20 mg/kg of cefsulodin [3-(4-carbamoyl-1-pyridiniomethyl)-7 beta-(D-alpha-sulfophenylacetamido)-ceph-3-em-4-carboxylate monosodium salt] was administered subcutaneously to mice, and intramuscularly to rats and dogs. The plasma and tissue levels reached the peak 15 approximately 30 minutes after administration. In mice and rats, no plasma levels were measurable 2 and 4 hours after administration. In dogs, the plasma levels were measurable 6 hours after administration. The level in the kidney of mice was slightly lower than the plasma level, while in rats and dogs, the level in the kidney was higher than the plasma level. The cefsulodin levels in the lung of rats and dogs were relatively high, and the level in mice was relatively low. The hepatic levels were very low in all test animal species. Cefsulodin was mainly excreted into the urine, and the excretion of cefsulodin into the bile was very slight.


Assuntos
Cefalosporinas/metabolismo , Animais , Bile/metabolismo , Cefalosporinas/administração & dosagem , Cefalosporinas/urina , Cães , Injeções Intramusculares , Injeções Subcutâneas , Absorção Intestinal , Masculino , Camundongos , Camundongos Endogâmicos , Ratos , Especificidade da Espécie , Fatores de Tempo
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