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1.
Theriogenology ; 167: 37-43, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33744770

RESUMO

The aberrant redox regulation and anti-oxidative defense is one of the main causes of age-induced decline in oocytes quality and embryo development in mammals. The present study aimed to elucidate the effect of glutathione ethyl ester (GSH-OEt), a cell-permeable glutathione (GSH) donor, on the developmental competence of oocytes in cows with advanced reproductive age. Oocytes were collected from cows aged 30-50 months or >120 months, which were defined as young or aged, respectively, and subjected to in vitro maturation (IVM) in the presence of 5 mM of GSH-OEt. In aged cows, the GSH level in follicular fluid was lower, and the intracellular levels of reactive oxygen species (ROS) in post-IVM oocytes was higher than those in young cows. GSH-OEt supplementation during IVM reduced the ROS contents of oocyte in aged cows but not in young cows. GSH-OEt treatment promoted the meiotic progression and increased the proportion of oocytes with mature cytoplasm containing evenly dispersed cortical granules in aged cows. After in vitro fertilization, the normal fertilization and development to the blastocyst stage were enhanced by GSH-OEt in aged cows to levels comparable to those in young cows. Further, oocyte maturation in the presence of GSH-OEt increased the proportion of diploid blastocyst in aged cows. In contrast, GSH-OEt failed to enhance the oocyte maturation, fertilization, and embryo development in young cows. Taken together, the exogenous supplementation of GSH-OEt during IVM modulated the age-related oxidative damage of bovine oocytes and improved the developmental competence of oocytes in aged cows. Oocytes presented a distinct response to GSH-OEt treatment depending on the donor age. GSH-OEt supplementation during IVM could be of practical value through the efficiency improvement of chromosomally normal embryo production in aged cows.


Assuntos
Glutationa , Oócitos , Animais , Blastocisto , Bovinos , Feminino , Fertilização in vitro/veterinária , Glutationa/análogos & derivados , Técnicas de Maturação in Vitro de Oócitos/veterinária , Oogênese
2.
Theriogenology ; 161: 243-251, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33340757

RESUMO

The present study aimed to elucidate the developmental kinetics, growth potential, and viability of bovine embryos produced in vitro with sexed semen. Bovine oocytes were fertilized in vitro using unsorted and X-sorted semen from the same Holstein bulls, and the kinetics of in vitro development were continuously monitored for 10 d through time-lapse cinematography. The blastocyst formation rate was lower in the X-sorted group than in the unsorted group (P < 0.01), whereas the normal fertilization rate did not differ between groups. Morphokinetic evaluation revealed that the incidence of blastomere fusion during the first cleavage division, termed reverse cleavage, was higher in the X-sorted group (P < 0.01). Furthermore, embryos produced with X-sorted semen showed slower growth throughout the developmental period than embryos produced with unsorted semen (P < 0.01). The cell number of the trophectoderm and inner cell mass of blastocysts was reduced in the X-sorted group (P < 0.01). In embryos that developed to the blastocyst stage, the hatchability (P < 0.05), chromosomal normality (P < 0.01), and survivability after the conventional frozen-thawing process (P < 0.05) were reduced in the X-sorted group compared to that in the unsorted group, indicating a compromised viability of embryos derived from X-sorted semen. Taken together, the first cleavage dysmorphism, delayed embryo growth, and impaired viability of embryos developed to the blastocyst stage may explain the mechanism of reduced fertility in embryos derived from sexed semen. The kinetic evaluation of early embryo development and de-selection of embryos presenting the aberrant first cleavage would be valid for clinical application to produce sexed embryos with high implantation potential.


Assuntos
Fertilização in vitro , Sêmen , Animais , Blastocisto , Bovinos , Desenvolvimento Embrionário , Fertilização in vitro/veterinária , Cinética , Masculino , Espermatozoides
3.
Theriogenology ; 133: 119-124, 2019 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-31085381

RESUMO

Time-lapse monitoring (TLM) has emerged as a novel technology for the continuous and noninvasive evaluation of embryos. TLM has revealed the prevalence of specific dysmorphisms such as abnormal development during the early-cleavage stage of embryos. However, little information is available on the prevalence and consequences of abnormal cleavage in bovine embryos. Hence, this study aimed to investigate growth potential of bovine embryos presenting abnormal cleavage, such as reverse cleavage (RC), direct cleavage (DC), and irregular and unsmooth ruffling of the oolema membrane (ruffling). Bovine embryos derived through in vitro fertilization (IVF) were cultured in the microwell culture dishes, and the kinetics of in vitro development were observed through TLM at 20-min intervals for 10 d. Approximately 36% of embryos that developed into a blastocyst presented abnormal cleavage. Morphokinetic evaluations revealed that RC, DC, and ruffling embryos showed slower development compared to embryos with normal cleavage (P < 0.01). Embryos with RC and DC, but not ruffling, revealed impaired hatchability (P < 0.05) with increased collapses of the blastocyst cavity until hatching (P < 0.0001). Moreover, the RC and DC embryos presented increased chromosomal aneuploidy (P < 0.05). These results suggest a compromised viability of embryos with RC and DC. This is the first report that clarified the effect of abnormal cleavage on the morphokinetics and growth potential of bovine IVF embryos. Results indicate that the kinetic evaluation of bovine embryos using the time-lapse imaging system will be beneficial for selecting embryos with a high viability.


Assuntos
Bovinos/embriologia , Desenvolvimento Embrionário , Aneuploidia , Animais , Blastocisto/citologia , Técnicas de Cultura Embrionária/veterinária , Feminino , Fertilização in vitro/veterinária , Imagem com Lapso de Tempo/veterinária
4.
Endoscopy ; 45(4): 316-9, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23345110

RESUMO

Strictures remaining after nonsurgical treatment for esophageal cancer are generally more refractory to endoscopic balloon dilation (EBD) when compared with anastomotic strictures. The aim of the present study was to evaluate the efficacy and safety of a radial incision and cutting (RIC) method for the treatment of refractory strictures after nonsurgical treatment of esophageal cancer. All subjects complained of grade 2 or worse dysphagia, even after at least 10 sessions of EBD. Between August 2009 and May 2012, eight consecutive patients with refractory esophageal stricture after nonsurgical treatments, including chemoradiotherapy (CRT) alone (n = 3), CRT followed by salvage endoscopic treatment (n = 3), or endoscopic submucosal dissection (ESD; n = 2), underwent the RIC procedure. After the RIC procedure, dysphagia in all the patients dramatically improved to grade 1 or 0 without any major complications; however, the long-term efficacy was unfavorable as only 37.5 % (3 /8) demonstrated adequate lumen patency at 3 months, and re-intervention was necessary in six patients (75 %).


Assuntos
Transtornos de Deglutição/cirurgia , Neoplasias Esofágicas/terapia , Estenose Esofágica/etiologia , Estenose Esofágica/cirurgia , Idoso , Quimiorradioterapia/efeitos adversos , Transtornos de Deglutição/etiologia , Dilatação , Estenose Esofágica/complicações , Humanos , Masculino , Pessoa de Meia-Idade , Fotoquimioterapia/efeitos adversos
5.
Eur J Pain ; 16(8): 1137-47, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22392567

RESUMO

BACKGROUND: Systemic administration of dexmedetomidine (DEX; selective α(2) -adrenoceptor agonist) is found to inhibit diffuse noxious inhibitory control in rats, now referred to as conditioned pain modulation (CPM) in humans. The present study was designed to investigate the effect of intravenous administration of DEX on CPM in humans. METHODS: There were two sequential sessions in this double blind, randomized study. The first session was the control with normal saline infusion (N(1st), L(1st), H(1st)). During the second session, three types of agents were infused: normal saline (N(2nd)); a low plasma concentration of DEX (0.04 ng/mL; L(2nd)); and a high plasma concentration of DEX (0.08 ng/mL; H(2nd)). The amplitude of somatosensory evoked potentials (ampSEP)s and the visual analogue scale of tooth pain (VASt) induced by electrical tooth stimulation were evaluated with and without conditioning CO(2) laser stimulation of the hand. The inhibition rate (% inhibition) was calculated [= (1-[ampSEP or VASt with conditioning stimuli]/[ampSEP or VASt without conditioning stimuli]) × 100] to compare the magnitude of the DEX effects on CPM. RESULTS: The inhibition rates of ampSEPs and VASt in Types N, L and H varied significantly, demonstrating a dose-dependent reduction of CPM effects of ampSEP and VASt during randomized DEX administration, consistent with results from animal studies. CONCLUSIONS: The present study shows that systemic administration of an α(2) -adrenoceptor agonist (DEX), less than the clinical dose, inhibited CPM in humans. These results may provide some mechanistic insight into why many chronic pain patients show impaired CPM.


Assuntos
Analgésicos não Narcóticos/farmacologia , Condicionamento Psicológico/efeitos dos fármacos , Dexmedetomidina/farmacologia , Medição da Dor/efeitos dos fármacos , Dor/tratamento farmacológico , Adulto , Analgésicos não Narcóticos/uso terapêutico , Córtex Cerebral/efeitos dos fármacos , Dexmedetomidina/uso terapêutico , Método Duplo-Cego , Estimulação Elétrica , Potenciais Somatossensoriais Evocados/efeitos dos fármacos , Feminino , Humanos , Masculino , Dente
6.
Phys Rev E Stat Nonlin Soft Matter Phys ; 86(6 Pt 1): 061138, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23367924

RESUMO

It has been known for some time that singular perturbation and reductive perturbation can be unified from the renormalization-group theoretical point of view: Reductive extraction of space-time global behavior is the essence of singular perturbation methods. Reductive renormalization was proposed to make this unification practically accessible; actually, this reductive perturbation is far simpler than most reduction methods, such as the rather standard scaling expansion. However, a rather cryptic exposition of the method seems to have been the cause of some trouble. Here, an explicit demonstration of the consistency of the reductive renormalization-group procedure is given for partial differentiation equations (of a certain type, including time-evolution semigroup type equations). Then, the procedure is applied to the reduction of a phase-field crystal equation to illustrate the streamlined reduction method. We conjecture that if the original system is structurally stable, the reductive renormalization-group result and that of the original equation are diffeomorphic.

12.
Rev Sci Instrum ; 79(10): 10F308, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19044621

RESUMO

The study of the mechanisms of both transport and fluctuations is one of the main issues of fusion plasma researches. Spatial fluctuation structure measurements are important for studying of cross correlation between the two fluctuations. Gold neutral beam probe systems are used in GAMMA 10 tandem mirror plasma device. Currently, the plasma potential and its fluctuations cannot be measured at different radial positions simultaneously. This paper presents the upgrade design of the 45 degrees electrostatic energy analyzer for the simultaneous multipoint measurements of plasma parameters.

13.
Rev Sci Instrum ; 79(10): 10F309, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19044622

RESUMO

A study of fluctuation is one of the main issues in fusion plasma researches. The potential and its fluctuation are measured by a gold neutral beam probe (GNBP) in the tandem mirror GAMMA10. Since there is no stable isotope ((197)Au approximately 100%), there are little measurement errors. GNBP system can measure the potential with about +/-30 V of error. The time and spatial resolutions are estimated to be about 3 micros and 5 mm, respectively. During the formation of axial confining potentials, the radial profiles of the potential and its fluctuation were successfully measured in GAMMA10. GNBP is a useful tool for the study of radial potential fluctuation directly in plasmas.

15.
Bioinformatics ; 21(6): 730-40, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15509613

RESUMO

MOTIVATION: Microarray experiments result in large-scale data sets that require extensive mining and refining to extract useful information. We demonstrate the usefulness of (non-metric) multidimensional scaling (MDS) method in analyzing a large number of genes. Applying MDS to the microarray data is certainly not new, but the existing works are all on small numbers (< 100) of points to be analyzed. We have been developing an efficient novel algorithm for non-metric MDS (nMDS) analysis for very large data sets as a maximally unsupervised data mining device. We wish to demonstrate its usefulness in the context of bioinformatics (unraveling relational patterns among genes from time series data in this paper). RESULTS: The Pearson correlation coefficient with its sign flipped is used to measure the dissimilarity of the gene activities in transcriptional response of cell-cycle-synchronized human fibroblasts to serum. These dissimilarity data have been analyzed with our nMDS algorithm to produce an almost circular relational pattern of the genes. The obtained pattern expresses a temporal order in the data in this example; the temporal expression pattern of the genes rotates along this circular arrangement and is related to the cell cycle. For the data we analyze in this paper we observe the following. If an appropriate preparation procedure is applied to the original data set, linear methods such as the principal component analysis (PCA) could achieve reasonable results, but without data preprocessing linear methods such as PCA cannot achieve a useful picture. Furthermore, even with an appropriate data preprocessing, the outcomes of linear procedures are not as clear-cut as those by nMDS without preprocessing.


Assuntos
Algoritmos , Fibroblastos/fisiologia , Perfilação da Expressão Gênica/métodos , Regulação da Expressão Gênica/fisiologia , Modelos Genéticos , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Fatores de Transcrição/metabolismo , Células Cultivadas , Humanos , Modelos Biológicos , Modelos Estatísticos , Análise Numérica Assistida por Computador , Reconhecimento Automatizado de Padrão/métodos , Transdução de Sinais/fisiologia
16.
J Theor Biol ; 213(3): 461-79, 2001 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-11735292

RESUMO

Honey bee division of labor is characterized by temporal polyethism, in which young workers remain in the hive and perform tasks there, whereas old workers perform more risky outside tasks, mainly foraging. We present a model of honey bee division of labor based on (1) an intrinsic process of behavioral development and (2) inhibition of development through social interactions among the workers in a colony. The model shows that these two processes can explain the main features of honey bee temporal polyethism: the correlation between age and task performance; the age at which a worker first forages and how this age varies among hives; the balanced allocation of workers to hive tasks and foraging; the recovery of a colony from demographic perturbations; and the differentiation of workers into different behavioral roles. The model provides a baseline picture of individual and colony behavior that can serve as the basis for studies of more fine-grained regulation of division of labor.


Assuntos
Abelhas/fisiologia , Comportamento Animal , Meio Social , Envelhecimento/fisiologia , Animais , Modelos Biológicos
17.
Kyobu Geka ; 54(11): 947-50, 2001 Oct.
Artigo em Japonês | MEDLINE | ID: mdl-11593733

RESUMO

According to increment of detection of the "small" size peripheral lung cancer measuring less than 20 mm in the greatest dimension, the "less" invasive VATS lobectomy has became widespread among the general thoracic surgeon. To decide on the indication of VATS lobectomy, the frequency of nodal metastasis and recurrence were examined in relation to size of the tumor. The diagnostic accuracy of nodal status in clinical and pathological examinations was 88% in the group with tumors less than 20 mm, 79% in the 21 to 30 mm group and 63% in the c-T2 group, respectively. Also, recurrencies were experienced more frequently in c-T2 (44%) than in c-T1 (19%). In our department, the VATS lobectomy was introduced under the condition as follows; the clinical stage should be limited to T1N0M0. Intraoperative histological examination of the locoregional lymph nodes is required to avoid the risk of local recurrence. In these limited conditions, the survival rate of VATS lobectomy is slightly superior to that of the standard thoracotomy in a same clinical stage. In the future, the application of this procedure should be investigated in older patients, and in more advanced cases.


Assuntos
Neoplasias Pulmonares/cirurgia , Pneumonectomia/mortalidade , Cirurgia Torácica Vídeoassistida , Humanos , Neoplasias Pulmonares/mortalidade , Neoplasias Pulmonares/patologia , Excisão de Linfonodo , Prognóstico , Taxa de Sobrevida , Cirurgia Torácica Vídeoassistida/mortalidade
18.
J Antibiot (Tokyo) ; 54(7): 573-81, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11560376

RESUMO

Bio-probes that inhibit the action of auxin are useful tools for the study of auxin signaling. To screen for specific inhibitors of auxin signaling, we used an Arabidopsis transgenic line harboring the auxin-inducible promoter derived from PS-IAA4/5 and the reporter gene, GUS (beta-glucuronidase). In this transgenic plant, the exogenous auxin specifically enhanced the expression of the GUS reporter gene. A novel 22-membered spiroketal-macrolide, yokonolide A (1), and related previously known compound, A82548A (2), were isolated from Streptomyces diastatochromogenes B59 as inhibitors of auxin inducible gene expression. The absolute structure of I was determined by detailed spectral analyses and chemical derivatization. 1 and 2 completely inhibited the auxin-induced transcription of the reporter gene at 5 and 1 microm, respectively. In contrast, 1 and 2 did not affect the translation of GUS reporter transcripts. In addition, 1 and 2 did not inhibit the gibberellin-induced alpha-amylase expression at 100 microM in barley aleurone cells. These results suggest that 1 and 2 specifically inhibit auxin signaling leading to auxin-mediated gene expression.


Assuntos
Antibacterianos/farmacologia , Antimetabólitos/farmacologia , Ácidos Indolacéticos/antagonistas & inibidores , Macrolídeos , Transdução de Sinais/efeitos dos fármacos , Streptomyces/química , Antibacterianos/química , Antibacterianos/isolamento & purificação , Antimetabólitos/química , Antimetabólitos/isolamento & purificação , Arabidopsis/efeitos dos fármacos , Arabidopsis/fisiologia , Fermentação , Espectroscopia de Ressonância Magnética , Conformação Molecular , Raízes de Plantas/efeitos dos fármacos , Streptomyces/classificação , Streptomyces/metabolismo
19.
Phys Rev E Stat Nonlin Soft Matter Phys ; 63(4 Pt 2): 046101, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11308906

RESUMO

It has been known for some time that singular perturbation and reductive perturbation can be unified from the renormalization-group (RG) theoretical point of view. However, renormalization-group approaches to singularly perturbed problems require explicit perturbation results, so they could be complicated practically. The approach proposed in this paper has considerably eliminated the need for explicit perturbation results, making the RG approach simpler than many conventional singular perturbation approaches. Consequently, we may assert that reductive extraction of global features of the problem is the essence of singular perturbation methods.

20.
Artigo em Inglês | MEDLINE | ID: mdl-11089068

RESUMO

It has been recognized that singular perturbation and reductive perturbation can be unified from the renormalization group (RG) theoretical point of view. However, the recognition has been only formal in the sense that it has not given us any new insight nor provided any new technical advantage over the usual RG approach. With our approach, the proto RG method proposed here, we can clearly show that system reduction is the key to singular perturbation methods. The approach also makes the calculation of singular perturbation results more transparent than the conventional RG approach. Consequently, for example, a consistent and easy RG derivation of the rotational covariant Newell-Whitehead-Segel equation is possible.

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