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1.
J Viral Hepat ; 23(9): 708-17, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27272497

RESUMO

Legalon SIL (SIL) is a chemically hydrophilized version of silibinin, an extract of milk thistle (Silybum marianum) seeds that has exhibited hepatoprotective and antiviral effectiveness against hepatitis C virus (HCV) in patients leading to viral clearance in combination with ribavirin. To elucidate the incompletely understood mode of action of SIL against HCV, mathematical modelling of HCV kinetics and human hepatocyte gene expression studies were performed in uPA-SCID-chimeric mice with humanized livers. Chronically HCV-infected mice (n = 15) were treated for 14 days with daily intravenous SIL at 469, 265 or 61.5 mg/kg. Serum HCV and human albumin (hAlb) were measured frequently, and liver HCV RNA was analysed at days 3 and 14. Microarray analysis of human hepatocyte gene expression was performed at days 0, 3 and 14 of treatment. While hAlb remained constant, a biphasic viral decline in serum was observed consisting of a rapid 1st phase followed by a second slower phase (or plateau with the two lower SIL dosings). SIL effectiveness in blocking viral production was similar among dosing groups (median ε = 77%). However, the rate of HCV-infected hepatocyte decline, δ, was dose-dependent. Intracellular HCV RNA levels correlated (r = 0.66, P = 0.01) with serum HCV RNA. Pathway analysis revealed increased anti-inflammatory and antiproliferative gene expression in human hepatocytes in SIL-treated mice. The results suggest that SIL could lead to a continuous second-phase viral decline, that is potentially viral clearance, in the absence of adaptive immune response along with increased anti-inflammatory and antiproliferative gene expression in human hepatocytes.


Assuntos
Antivirais/farmacologia , Hepatite C/tratamento farmacológico , Hepatite C/virologia , Fígado/patologia , Fígado/virologia , Silimarina/farmacologia , Carga Viral , Administração Intravenosa , Animais , Antivirais/administração & dosagem , Linhagem Celular , Modelos Animais de Doenças , Perfilação da Expressão Gênica , Hepacivirus/isolamento & purificação , Humanos , Camundongos SCID , Análise em Microsséries , Modelos Teóricos , RNA Viral/análise , Análise de Sequência de DNA , Albumina Sérica/análise , Silibina , Silimarina/administração & dosagem , Resultado do Tratamento
2.
J Urol ; 204(5): 1068, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32698716

Assuntos
Noctúria , Humanos
3.
J Viral Hepat ; 22(2): 166-74, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24930407

RESUMO

Treatment success of chronic hepatitis C virus genotype 1 infection has improved with the advent of telaprevir plus peg-interferon/ribavirin triple combination therapy. However, the effect of inosine triphosphatase (ITPA) polymorphism on dose reduction during triple therapy, especially during the postmarketing phase, has not been sufficiently evaluated. We analysed 273 patients with genotype 1 infection who were treated with triple therapy and assessed the effect of the ITPA polymorphism on dose reduction. ITPA and IFNL4 SNP genotypes were determined by the Invader assay. A stepwise multivariate regression analysis was performed to identify factors associated with outcome of the therapy. The overall sustained viral response (SVR) rate 12 weeks after the end of therapy was 80.2% (219/273). Decline of haemoglobin was significantly faster, and ribavirin was more extensively reduced in patients with ITPA SNP rs1127354 genotype CC than CA/AA. Extensive reduction of ribavirin resulted in mild reduction of telaprevir and peg-interferon, but no significant increase in viral breakthrough. Although the amount of telaprevir given was slightly higher in CA/AA patients, the total dose of peg-interferon and the SVR rate did not differ between the two groups. Multivariate analysis showed that IFNL4 but not ITPA SNP genotype, platelet count and peg-interferon adherence were significantly associated with outcome of therapy. Postmarketing-phase triple therapy resulted in a high SVR rate in spite of extensive ribavirin dose reduction in a diverse patient population, indicating the importance of treatment continuation and appropriate management of adverse events.


Assuntos
Antivirais/administração & dosagem , Hepatite C Crônica/tratamento farmacológico , Interferon-alfa/administração & dosagem , Oligopeptídeos/administração & dosagem , Polimorfismo de Nucleotídeo Único , Pirofosfatases/genética , Ribavirina/administração & dosagem , Adulto , Idoso , Quimioterapia Combinada/métodos , Feminino , Genótipo , Técnicas de Genotipagem , Hepacivirus/classificação , Hepacivirus/genética , Hepacivirus/isolamento & purificação , Humanos , Interleucinas/genética , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento , Adulto Jovem
4.
NPJ Microgravity ; 9(1): 83, 2023 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-37852993

RESUMO

We review recent in situ solidification experiments using nonfaceted model transparent alloys in science-in-microgravity facilities onboard the International Space Station (ISS), namely the Transparent Alloys (TA) apparatus and the Directional Solidification Insert of the DEvice for the study of Critical Liquids and Crystallization (DECLIC-DSI). These directional-solidification devices use innovative optical videomicroscopy imaging techniques to observe the spatiotemporal dynamics of solidification patterns in real time in large samples. In contrast to laboratory conditions on ground, microgravity guarantees the absence or a reduction of convective motion in the liquid, thus ensuring a purely diffusion-controlled growth of the crystalline solid(s). This makes it possible to perform a direct theoretical analysis of the formation process of solidification microstructures with comparisons to quantitative numerical simulations. Important questions that concern multiphase growth patterns in eutectic and peritectic alloys on the one hand and single-phased, cellular and dendritic structures on the other hand have been addressed, and unprecedented results have been obtained. Complex self-organizing phenomena during steady-state and transient coupled growth in eutectics and peritectics, interfacial-anisotropy effects in cellular arrays, and promising insights into the columnar-to-equiaxed transition are highlighted.

5.
Sci Rep ; 9(1): 9862, 2019 07 08.
Artigo em Inglês | MEDLINE | ID: mdl-31285481

RESUMO

An estuary is a dynamic environment where marine and fluvial processes meet to form complex and transient morphology. The estuary morphology is largely determined by net sediment transport by two-way tidal flows, but the hydrodynamics also depends on the morphology of the tidal channels. The estuary inherently accommodates cyclic processes that are internally generated through hydro-morphodynamic interactions. In addition, the estuary evolves in response to changes in external forces by natural and anthropogenic factors. Morphological changes under the different controls often hinder the comprehension of the evolutionary processes of estuaries. Here we explored morphological changes in the Sittang River estuary, Myanmar, which has great morphological dynamism from extreme tidal energy and large sediment inputs, through field surveys and satellite imagery analysis. We identify an autocyclic process in a sedimentary system driving large-scale channel migration in decadal to multidecadal cycles. We show that drastic changes of the estuary morphology occasionally occur with rapid bank erosion through modulation of the cyclic channel migration under conflicting tidal and fluvial forces. This extreme case with minimal human intervention highlights channel migration as a key process in morphological evolution of tide-dominated estuaries undergoing active infilling.

6.
Phys Rev E Stat Nonlin Soft Matter Phys ; 75(2 Pt 1): 021602, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17358348

RESUMO

We present a feedback control scheme to stabilize unstable cellular patterns during the directional solidification of a binary alloy. The scheme is based on local heating of cell tips which protrude ahead of the mean position of all tips in the array. The feasibility of this scheme is demonstrated using phase-field simulations and, experimentally, using a real-time image processing algorithm, to track cell tips, coupled with a movable laser spot array device to heat the tips locally. We demonstrate, both numerically and experimentally, that spacings well below the threshold for a period-doubling instability can be stabilized. As predicted by the numerical calculations, cellular arrays become stable with uniform spacing through the feedback control which is maintained with minimal heating.

7.
J Interferon Cytokine Res ; 20(2): 217-24, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10714558

RESUMO

Interleukin-18 (IL-18) is known to synergistically enhance murine natural killer (NK) cell activity in vitro when combined with either IL-12 or IL-2. However, it has also been demonstrated that simultaneous administration of IL-18 and IL-12 to mice induces extraordinarily large amounts of interferon-gamma (IFN-gamma) in the serum. In this study, we examined the effects of a combination of IL-18 and IL-2 on in vivo NK cell activation in parallel with the induction of toxicity. In contrast to the IL-18 and IL-12 combination, the combined administration of IL-18 and IL-2 to BALB/c mice for 3 days induced neither high levels of IFN-gamma production nor other visible side effects. When compared with treatment with IL-18 or IL-2 alone, the combined treatment resulted in a significant increase in the number of DX-5 (pan-NK cells marker)-positive cells in spleens and a marked enhancement of splenic NK activity, as determined by standard cytotoxicity assays. Enhanced splenic cytotoxicity generated in the mice treated with both IL-18 and IL-2 was also observed against syngeneic Colon 26 adenocarcinoma cells. Consistent with this in vitro observation, combined treatment produced a significantly stronger inhibitory effect on the pulmonary metastases following i.v. injection of Colon 26 tumor cells than treatment with either cytokine alone. These results suggest that IL-18 combined with IL-2 potentiates in vivo NK cell activity and contributes to inhibition of tumor metastasis without inducing significant toxicity.


Assuntos
Interferon gama/biossíntese , Interleucina-18/administração & dosagem , Interleucina-2/administração & dosagem , Células Matadoras Naturais/efeitos dos fármacos , Células Matadoras Naturais/imunologia , Animais , Sinergismo Farmacológico , Feminino , Interleucina-12/administração & dosagem , Fígado/citologia , Fígado/efeitos dos fármacos , Fígado/imunologia , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/imunologia , Neoplasias Pulmonares/secundário , Camundongos , Camundongos Endogâmicos BALB C , Proteínas Recombinantes/administração & dosagem , Baço/citologia , Baço/efeitos dos fármacos , Baço/imunologia , Células Tumorais Cultivadas
8.
Clin Exp Metastasis ; 18(1): 37-43, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11206836

RESUMO

A new ex vivo method for assaying adhesion of cancer cells to the greater omentum has been developed using mouse greater omentum and [3H]labelled human gastric and mouse colorectal cancer cells. Since the adhesion rates were found to increase up to 18 h and labelled cells seemed to be stable during the period, the present method could be useful for investigating adhesion of cancer cells to the greater omentum, which must occur at the first step of the peritoneal dissemination. The adhesion of cancer cells to the greater omentum was inhibited by a series of chemically synthesized oligosaccharides and Gal beta1,3[3OMeGal beta1,4GlcNAc beta1,6]alphaBn was found to be the best inhibitor. The anti-tumor effect of this novel tetrasaccharide in vivo was shown in preliminary experiments using Balb/c mice and colon26 cells.


Assuntos
Adesão Celular/efeitos dos fármacos , Oligossacarídeos/farmacologia , Omento/patologia , Animais , Sequência de Carboidratos , Separação Celular , Neoplasias do Colo/patologia , Neoplasias do Colo/ultraestrutura , Citometria de Fluxo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Microscopia Eletrônica de Varredura , Dados de Sequência Molecular , Metástase Neoplásica , Oligossacarídeos/química , Cavidade Peritoneal/patologia , Células Tumorais Cultivadas
9.
Proc Biol Sci ; 261(1362): 367-73, 1995 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-8587879

RESUMO

Theories of object recognition have emphasized the information conveyed by shape information, whereas theories of face recognition have emphasized properties of superficial features. In the experiments reported here we used novel technology to investigate the relative contributions of shape and superficial colour information to simple categorization decisions about the sex and 'race' of faces. The results show that both shape and colour provide useful information for these decisions; shape information was particularly useful for race decisions while colour dominated sex decisions. When both sources of information were combined, the dominant source depended on viewpoint, with angled views emphasizing the contribution of shape and the full-face view colour. The results are discussed within the context of theories of face recognition and their implications for telecommunication applications are considered.


Assuntos
Face/anatomia & histologia , Percepção de Forma , Grupos Raciais , Caracteres Sexuais , Pigmentação da Pele , Adulto , Análise de Variância , Povo Asiático , Feminino , Humanos , Japão , Masculino , População Branca
10.
Proc Biol Sci ; 267(1459): 2239-45, 2000 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-11413638

RESUMO

Full-face masks, worn by skilled actors in the Noh tradition, can induce a variety of perceived expressions with changes in head orientation. Out-of-plane rotation of the head changes the two-dimensional image characteristics of the face which viewers may misinterpret as non-rigid changes due to muscle action. Three experiments with Japanese and British viewers explored this effect. Experiment 1 confirmed a systematic relationship between vertical angle of view of a Noh mask and judged affect. A forward tilted mask was more often judged happy, and one backward tilted more often judged sad. This effect was moderated by culture. Japanese viewers ascribed happiness to the mask at greater degrees of backward tilt with a reversal towards sadness at extreme forward angles. Cropping the facial image of chin and upper head contour reduced the forward-tilt reversal. Finally, the relationship between head tilt and affect was replicated with a laser-scanned human face image, but with no cultural effect. Vertical orientation of the head changes the apparent disposition of facial features and viewers respond systematically to these changes. Culture moderates this effect, and we discuss how perceptual strategies for ascribing expression to familiar and unfamiliar images may account for the differences.


Assuntos
Expressão Facial , Adolescente , Adulto , Drama , Feminino , Humanos , Japão , Masculino , Pessoa de Meia-Idade , Percepção Visual
11.
Am J Cardiol ; 70(13): 1190-4, 1992 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-1414945

RESUMO

The pulmonary vein flow velocity-time profile would be equivalent to the pulmonary vein flow volume-time profile, provided that the cross-sectional area of the pulmonary vein remains unchanged during 1 cardiac cycle. The systolic fraction of the pulmonary vein flow velocity-time integral, a ratio of velocity-time integral of the S wave to the sum of velocity-time integrals of the S and D waves, represents the ratio of left atrial storage volume to left ventricular stroke volume. This systolic fraction may help early filling of the left ventricle through an appropriate storage of blood and generation of driving pressure in the left atrium. Because early filling of the left ventricle is progressively impaired with age, it was hypothesized that this systolic fraction is increased with age. Forty-four noncardiac surgical patients (age range 17 to 70 years) who underwent transesophageal Doppler echocardiography under general anesthesia were studied, and left upper pulmonary vein flow and mitral inflow velocities were recorded. The ratio of peak velocity of the E wave to that of the A wave of mitral inflow velocity-time profile (y) decreased with age (y = -0.0245 x age + 2.41; r = -0.672, p < 0.01). Systolic fraction (y) increased with age (y = 0.00373 x age + 0.514; r = 0.656, p < 0.01). The age-related increase in the systolic fraction of pulmonary vein flow velocity-time integral may account for the compensation for impaired early filling of the left ventricle in elderly patients.


Assuntos
Envelhecimento/fisiologia , Átrios do Coração/fisiopatologia , Veias Pulmonares/fisiopatologia , Adolescente , Adulto , Idoso , Velocidade do Fluxo Sanguíneo/fisiologia , Ecocardiografia Doppler/métodos , Esôfago , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Veias Pulmonares/diagnóstico por imagem , Sístole/fisiologia
12.
Cognition ; 62(2): 201-22, 1997 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9141907

RESUMO

How we recognize faces despite rotations in depth is of great interest to psychologists, computer scientists and neurophysiologists because of the accuracy of human performance despite the intrinsic difficulty of the task. Three experiments are reported here which used three-dimensional facial surface representations to investigate the effects of rotations in depth on a face recognition task. Experiment 1, using "shape only" representations, showed that all the views used (full-face, three-quarter and profile) were equally well recognized when all had been learned. Performance was better when the same views were presented in an animated sequence rather than at random, suggesting that structure-from-motion provides useful information for recognition. When stimuli were presented inverted, performance was worse and there were differences in the recognizability of views, demonstrating that the familiarity of upright faces affects generalization across views. Experiments 2 and 3 investigated generalization from single views and found performance to be dependent on learned view. In both experiments, generalization from learned full-face fell off with increasing angle of rotation. With shape only stimuli, three-quarter views generalized well to each other, even when inverted but for profiles generalization was equally bad to all unlearned views. This difference may be explained because of the particular relationship of the profile to the axis of symmetry. In Experiment 3, addition of information about superficial properties including color and texture facilitated performance, but patterns of generalization remained substantially the same, emphasizing the importance of underlying shape information. However, generalization from the three-quarter view became viewpoint invariant and there was some evidence for better generalization between profiles. The results are interpreted as showing that three-dimensional shape information is fundamental for recognition across rotations in depth although superficial information may also be used to reduce viewpoint dependence.


Assuntos
Percepção de Profundidade , Expressão Facial , Orientação , Reconhecimento Visual de Modelos , Adulto , Feminino , Generalização Psicológica , Humanos , Masculino , Rememoração Mental , Resolução de Problemas
13.
Chest ; 104(6): 1911-3, 1993 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8252986

RESUMO

A patient with a Björk-Shiley mitral prosthesis developed progressive heart failure without heart murmur and hemolysis. The prosthetic dehiscence was not diagnosed using transthoracic echocardiography, but transesophageal echocardiography. The regurgitant signals revealed laminar flow pattern with large regurgitant orifice. In patients with mitral prosthetic dehiscence with laminar flow pattern, transesophageal echocardiography can provide reliable diagnostic information.


Assuntos
Ecocardiografia Transesofagiana , Próteses Valvulares Cardíacas , Insuficiência da Valva Mitral/diagnóstico por imagem , Valva Mitral/cirurgia , Deiscência da Ferida Operatória/diagnóstico por imagem , Adulto , Velocidade do Fluxo Sanguíneo , Humanos , Masculino , Insuficiência da Valva Mitral/etiologia , Reoperação , Deiscência da Ferida Operatória/complicações
14.
Diagn Microbiol Infect Dis ; 39(2): 95-7, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11248521

RESUMO

We have recently developed an on-site diagnostic kit for H. pylori infection using urine (utilizing immunochromatographic method employing a nitrocellulose membrane coated by extracted H. pylori antigen). Accordingly, we investigated its usefulness in 155 consecutive dyspeptic patients using the 13C urea breath test as a gold standard and further compared its performance with two commercially available rapid diagnostic kits that use whole blood (Helisal Rapid Blood, and ImmunoCard H. pylori). As the results, the urine based on-site diagnostic kit provided 95.9% sensitivity and 87.9% specificity with 92.9% accuracy, which were comparable or even better than that of both rapid whole blood tests, suggesting its usefulness in screening of H. pylori infection.


Assuntos
Infecções por Helicobacter/diagnóstico , Infecções por Helicobacter/microbiologia , Helicobacter pylori/isolamento & purificação , Urina/microbiologia , Antígenos de Bactérias/sangue , Testes Respiratórios , Humanos , Kit de Reagentes para Diagnóstico , Sensibilidade e Especificidade , Ureia/metabolismo
15.
Vision Res ; 41(9): 1179-208, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11292507

RESUMO

Pictures of facial expressions from the Ekman and Friesen set (Ekman, P., Friesen, W. V., (1976). Pictures of facial affect. Palo Alto, California: Consulting Psychologists Press) were submitted to a principal component analysis (PCA) of their pixel intensities. The output of the PCA was submitted to a series of linear discriminant analyses which revealed three principal findings: (1) a PCA-based system can support facial expression recognition, (2) continuous two-dimensional models of emotion (e.g. Russell, J. A. (1980). A circumplex model of affect. Journal of Personality and Social Psychology, 39, 1161-1178) are reflected in the statistical structure of the Ekman and Friesen facial expressions, and (3) components for coding facial expression information are largely different to components for facial identity information. The implications for models of face processing are discussed.


Assuntos
Expressão Facial , Processamento de Imagem Assistida por Computador , Adolescente , Adulto , Sinais (Psicologia) , Análise Discriminante , Emoções/fisiologia , Feminino , Percepção de Forma/fisiologia , Humanos , Masculino , Memória/fisiologia
16.
Phys Rev E Stat Nonlin Soft Matter Phys ; 66(5 Pt 1): 051709, 2002 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-12513505

RESUMO

We present an experimental study of the surface effects (interactions with the container walls) during the nucleation and growth of smectic-B (SmB) crystals from the nematic in free growth and directional solidification of a mesogenic molecule [C4H9-(C6H10)2CN] called CCH4 in thin (of thickness in the 10-microm range) samples. We follow the dynamics of the system in real time with a polarizing microscope. The inner surfaces of the glass-plate samples are coated with polymeric films, either rubbed polyimid (PI) films or mono-oriented poly(tetrafluoroethylene) (PTFE) films deposited by friction at high temperature. The orientation of the nematic and the smectic-B is planar. In PI-coated samples, the orientation effect of SmB crystals is mediated by the nematic, whereas, in PTFE-coated samples, it results from a homoepitaxy phenomenon occurring for two degenerate orientations. A recrystallization phenomenon partly destroys the initial distribution of crystal orientations. In directional solidification of polycrystals in PTFE-coated samples, a particular dynamics of faceted grain boundary grooves is at the origin of a dynamical mechanism of grain selection. Surface effects also are responsible for the nucleation of misoriented terraces on facets and the generation of lattice defects in the solid.

17.
Phys Rev E Stat Nonlin Soft Matter Phys ; 65(1 Pt 1): 011702, 2002 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11800702

RESUMO

We present an experimental study of the directional-solidification patterns of a nematic-smectic-B front. The chosen system is C4H9-(C6H10)2CN (in short, CCH4) in 12 microm-thick samples, and in the planar configuration (director parallel to the plane of the sample). The nematic-smectic-B interface presents a facet in one direction-the direction parallel to the smectic layers--and is otherwise rough and devoid of forbidden directions. We measure the Mullins-Sekerka instability threshold and establish the morphology diagram of the system as a function of the solidification rate V and the angle straight theta(0) between the facet and the isotherms. We focus on the phenomena occurring immediately above the instability threshold when straight theta(0) is neither very small nor close to 90 degrees. Under these conditions, we observe drifting shallow cells and a type of solitary wave, called "faceton," which consists essentially of an isolated macroscopic facet traveling laterally at such a velocity that its growth rate with respect to the liquid is small. Facetons may propagate either in a stationary or an oscillatory way. The detailed study of their dynamics casts light on the microscopic growth mechanisms of the facets in this system.

18.
Phys Rev E Stat Nonlin Soft Matter Phys ; 66(3 Pt 1): 030501, 2002 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12366091

RESUMO

We demonstrate by both experiments and phase-field simulations that lamellar eutectic growth can be stable for a wide range of spacings below the point of minimum undercooling at low velocity, contrary to what is predicted by existing stability analyses. This overstabilization can be explained by relaxing Cahn's assumption that lamellae grow locally normal to the eutectic interface.

19.
J Biosci Bioeng ; 90(5): 555-60, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-16232909

RESUMO

To reveal the mechanism of the production of acetate by sake yeast (Saccharomyces cerevisiae), the expression of genes encoding aldehyde dehydrogenase (ALD), acetyl-CoA synthetase (ACS) and acetyl-CoA hydrolase (ACH), which are related to acetate production, was investigated. Northern blot analysis using total RNA of sake yeast isolated from sake mash revealed that all of the tested genes, ACS1, ACS2, ALD2/3, ALD4, ALD6 and ACH1, were transcribed during sake fermentation. Transcription of ALD2/3 was detected only in the early stage of sake fermentation. A static culture of sake yeast in hyperosmotic media including 1 M sorbitol or 20% glucose resulted in high acetate production and increased transcription of ALD2/3. This is the same result as reported in an aerobic condition, and induction of ALD2/3 seemed to be one reason for high acetate production at high glucose concentration during fermentation. Overexpression of ACS2 resulted in low acetate production both during small-scale sake fermentation and in a static liquid culture. On the other hand, over-expression of ACS1 did not change acetate productivity significantly in a static culture. These results indicate that ALD2/3 and ACS2 play important roles for acetate production during sake fermentation.

20.
Theriogenology ; 50(3): 365-75, 1998 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10732132

RESUMO

This study was undertaken to determine the effects of glucose, antioxidants and different oxygen tensions on the development of bovine embryos cultured in modified synthetic oviduct fluid (m-SOF) medium. In vitro matured (IVM) and fertilized (IVF) oocytes were incubated for 48 h. Embryos reaching at least the 4-cell stage were selected for further culture under various conditions for 6 d. Supplementing the m-SOF media with 4.5 mM glucose resulted in a significantly lower (P < 0.01) embryo developmental rate (21%; Day 8) than was obtained with 1.5 mM glucose (58%; Day 8) or no glucose (53%; Day 8). Antioxidants such as SOD, catalase and mannitol had no positive effect on embryo development in m-SOF medium supplemented with 1.5 mM glucose. However, in m-SOF medium supplemented with 4.5 mM glucose, SOD and mannitol significantly (P < 0.05) improved embryo development: SOD increased the developmental rate from 19 to 35% (Day 8), while mannitol increased it from 13 to 30% (Day 8). Low oxygen concentration improved embryo development significantly (P < 0.05) in m-SOF medium supplemented with 4.5 mM glucose (low O2: 31% vs high O2: 14%; Day 8) but not 0 mM glucose (low O2: 58% vs high O2: 55%; Day 8). Our data suggest that low concentration of glucose during culture of bovine embryos is beneficial, and that generation of free oxygen radicals is partly caused by a high concentration of glucose in the medium.


Assuntos
Antioxidantes/farmacologia , Bovinos/embriologia , Desenvolvimento Embrionário e Fetal/efeitos dos fármacos , Fertilização in vitro/veterinária , Glucose/administração & dosagem , Animais , Blastocisto , Catalase/farmacologia , Técnicas de Cultura , Feminino , Manitol/farmacologia , Oxigênio/administração & dosagem , Superóxido Dismutase/farmacologia
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