Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 26
Filtrar
1.
Animals (Basel) ; 14(5)2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38473109

RESUMO

This study analyzed 5322 camera trap photographs from Halla Mountain Wetland, documenting 1427 independent bird sightings of 26 families and 49 species of Passeriformes. Key observations include morning activities in Cyanoptila cyanomelana and Horornis canturians and afternoon activity in Muscicapa dauurica and Phoenicurus auroreus. Wetlands were significantly preferred (P_i = 0.398) despite their smaller area, contrasting with underutilized grasslands (P_i = 0.181). Seasonal activity variations were notable, with overlap coefficients ranging from 0.08 to 0.81 across species, indicating diverse strategies in resource utilization and thermoregulation. Population density was found to be a critical factor in habitat usage, with high-density species showing more consistent activity patterns. The study's results demonstrate the ecological adaptability of Passeriformes in the Halla Mountain Wetland while highlighting the limitations of camera trapping methods. These limitations include their fixed field of view and intermittent recording capability, which may not fully capture the spectrum of complex avian behaviors. This research underlines the need for future studies integrating various methodologies, such as direct observation and acoustic monitoring, to gain a more comprehensive understanding of avian ecology.

2.
Toxics ; 11(4)2023 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-37112528

RESUMO

The female reproductive system becomes fertile through the action of hormones involved in the hypothalamic-pituitary-ovarian axis. On the other hand, estrogen-like endocrine disruptors released into the environment come into contact with humans by various routes and affect the reproductive system. Exposure to these chemicals can cause problems with the reproductive process, from egg ovulation to implantation, or cause female reproductive diseases. These reproductive problems cause infertility. Decamethylcyclopentasiloxane (D5) is used for lubrication in silicone polymers, households, and personal care products. In the case of D5, it is discharged through factory wastewater and can bioaccumulate. Therefore, it accumulates in the human body. In this study, D5 was administered orally for four weeks to determine the effects of D5 on the reproductive process. As a result, D5 increases the number of follicles in the ovary and suppresses the expression of genes related to the growth of follicles. In addition, it increases the gonadotropin hormone, inducing estradiol enhancement and progesterone reduction. Because of these changes in the reproductive system when exposed to D5, the industry should reconsider using D5.

3.
Gut Liver ; 17(6): 853-862, 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-36588524

RESUMO

Background/Aims: This study aimed to develop a rehabilitation program for musculoskeletal pain experienced by gastrointestinal endoscopists and to investigate its usefulness. Methods: This was a multicenter cohort study. During the first 2 weeks, a questionnaire regarding daily workload and musculoskeletal symptoms was administered. Then, a rehabilitation program including equipment/posture correction and stretching was conducted during the remaining 6 weeks. Follow-up daily workload and musculoskeletal symptom surveys were distributed during the last 2 weeks. The program satisfaction survey was performed at the 6th and 8th weeks. Results: Among 118 participants (69 men), 94% (n=111) complained of musculoskeletal pain at baseline. Various hospital activities at baseline were associated with multisite musculoskeletal pain, whereas only a few workloads were correlated with musculoskeletal pain after the rehabilitation program. Follow-up musculoskeletal pain was negatively correlated with equipment/posture program performance; arm/elbow pain was negatively correlated with elbow (R=-0.307) and wrist (R=-0.205) posture; leg/foot pain was negatively correlated with monitor position, shoulder, elbow, wrist, leg, and foot posture. Higher performance in the scope position (86.8% in the improvement vs 71.3% in the aggravation group, p=0.054) and table height (94.1% vs 79.1%, p=0.054) were associated with pain improvement. An increased number of colonoscopy procedures (6.27 in the aggravation vs 0.02 in the improvement group, p=0.017) was associated with pain aggravation. Most participants reported being average (32%) or satisfied (67%) with the program at the end of the study. Conclusions: Our rehabilitation program is easily applicable, satisfactory, and helpful for improving the musculoskeletal pain experienced by gastrointestinal endoscopists.


Assuntos
Dor Musculoesquelética , Doenças Profissionais , Masculino , Humanos , Estudos Prospectivos , Estudos de Coortes , Fatores de Risco , Doenças Profissionais/diagnóstico
4.
Food Chem Toxicol ; 164: 113070, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35483486

RESUMO

Exposure to neurodevelopmental toxicants can cause permanent brain injury. Hance, determining the neurotoxicity of unknown substances is essential for the safety of substance. As an alternative method to animal studies, developmental neurotoxicity test (DNT) and the first discriminant function (DF) were established in previous study. This study aimed to increase the predictability of the DNT method and perform a mobility test. Two endpoints of 29 newly investigated substances were used to establish a second-generation DF (2nd GDF). As two endpoints, the half-inhibitory concentration of the cell viability (IC50) was determined using a cell counting kit-8 assay. The half-inhibitory concentration of differentiation (ID50) was determined by measuring the green fluorescent protein (GFP) intensity in 46C cells. The substances were treated dose-dependently to measure IC50 and ID50. The 2nd GDF classified 29 chemicals accurately as toxic and non-toxic. Four participants of three independent laboratories were enrolled to test the mobility. The results of the test set were highly accurate in reproducibility (100% of accuracy, sensitivity, and specificity) and mobility (accuracy 93.33%, sensitivity 90.91%, and specificity 100%). In conclusion, the protocol is transferable, reproducible, and accurate. Therefore, this could be a standardizing method for determining a neurotoxicant as an alternative for animal experiments.


Assuntos
Síndromes Neurotóxicas , Testes de Toxicidade , Animais , Diferenciação Celular , Sobrevivência Celular , Humanos , Síndromes Neurotóxicas/etiologia , Reprodutibilidade dos Testes , Testes de Toxicidade/métodos
5.
Animals (Basel) ; 12(8)2022 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-35454244

RESUMO

Non-native species threaten native ecosystems and species, particularly on islands where rates of endemism and vulnerability to threats are high. Understanding species invasion will aid in providing insights into ecological and evolutionary processes. To identify the non-native sika deer (Cervus nippon) population in Jeju, South Korea, and their phylogenetic affinities, we collected tissue samples from roadkill and the World Natural Heritage Headquarters in Jeju. Mitochondrial DNA cytochrome B (CytB) gene sequences were analyzed to determine two distinct CytB haplotypes. Phylogenetic analysis using maximum likelihood tree revealed two haplotypes of CytB clustered into two different groups representing two subspecies: C. n. yakushimae, native to Japan, and C. n. taiouanus, native to Taiwan. The tentative divergence time between the two subspecies was estimated at 1.81 million years. Our study confirmed that the two subspecies of sika deer are sympatric in the natural ecosystem of Jeju Island. This study provides valuable information to help government and conservation agencies understand alien species and determine control policies for conserving native biodiversity in South Korea.

6.
Int J Mol Sci ; 22(23)2021 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-34884750

RESUMO

Cyclic siloxane octamethylcyclotetrasiloxane (D4) has raised concerns as an endocrine-disrupting chemical (EDC). D4 is widely used in detergent products, cosmetics, and personal care products. Recently, robust toxicological data for D4 has been reported, but the adverse effects of D4 on brain development are unknown. Here, pregnant mice on gestational day 9.5 were treated daily with D4 to postnatal day 28, and the offspring mice were studied. The prenatal D4-treated mice exhibited cognitive dysfunction, limited memory, and motor learning defect. Moreover, prenatal D4 exposure reduced the proliferation of neuronal progenitors in the offspring mouse brain. Next, the mechanisms through which D4 regulated the cell cycle were investigated. Aberrant gene expression, such as cyclin-dependent kinases CDK6 and cyclin-dependent kinase inhibitor p27, were found in the prenatal D4-treated mice. Furthermore, the estrogen receptors ERa and ERb were increased in the brain of prenatal D4-treated mice. Overall, these findings suggest that D4 exerts estrogen activity that affects the cell cycle progression of neuronal progenitor cells during neurodevelopment, which may be associated with cognitive deficits in offspring.


Assuntos
Disruptores Endócrinos/toxicidade , Células-Tronco Neurais/efeitos dos fármacos , Efeitos Tardios da Exposição Pré-Natal/patologia , Efeitos Tardios da Exposição Pré-Natal/fisiopatologia , Siloxanas/toxicidade , Animais , Comportamento Animal/efeitos dos fármacos , Encéfalo/efeitos dos fármacos , Encéfalo/crescimento & desenvolvimento , Encéfalo/patologia , Proteínas de Ciclo Celular/metabolismo , Linhagem Celular , Proliferação de Células , Cognição/efeitos dos fármacos , Disruptores Endócrinos/administração & dosagem , Feminino , Técnicas de Introdução de Genes , Proteínas de Fluorescência Verde/genética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Modelos Neurológicos , Atividade Motora/efeitos dos fármacos , Células-Tronco Embrionárias Murinas/efeitos dos fármacos , Células-Tronco Embrionárias Murinas/metabolismo , Células-Tronco Embrionárias Murinas/patologia , Células-Tronco Neurais/citologia , Células-Tronco Neurais/fisiologia , Neurogênese/efeitos dos fármacos , Gravidez , Efeitos Tardios da Exposição Pré-Natal/psicologia , Fatores de Transcrição SOXB1/genética , Siloxanas/administração & dosagem , Comportamento Social
7.
Reprod Toxicol ; 104: 96-105, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34273508

RESUMO

Developmental toxicity tests have been generated by applying the embryonic stem cell tests at the European Centre for the Validation of Alternative Methods, or by using the embryoid body test in our laboratory. This study was undertaken to explore novel developmental neurotoxicity (DNT) assay, using a Sox1-GFP cell line (mouse embryonic stem cells with an endogenous Sox1-GFP reporter). The expression of Sox1, a marker for neuroepithelial cells, is detected by green fluorescence, and the fluorescence intensity is a critical factor for achieving neuronal differentiation. Sox1-GFP cells cultured for 24 h were exposed to eleven neurotoxicants and four non-neurotoxicants. CCK-8 assays were performed to determine IC50 values after 48 h of chemical treatment. The fluorescence intensity of GFP was measured 4 days after treating the cells, and it was observed to decrease after exposure to neurotoxicants at higher concentrations, thereby indicating that the neuronal differentiation of Sox1-GFP cells is inhibited by the chemicals. Taken together, the results obtained in this study provide a model for DNT using embryonic stem cells, which may be applied to evaluate the toxicity of new chemicals or new drug candidates.


Assuntos
Neurônios/efeitos dos fármacos , Fatores de Transcrição SOXB1/metabolismo , Testes de Toxicidade/métodos , Animais , Diferenciação Celular , Linhagem Celular , Sobrevivência Celular , Células Cultivadas , Corpos Embrioides/metabolismo , Proteínas de Fluorescência Verde/metabolismo , Camundongos , Células-Tronco Embrionárias Murinas/metabolismo , Células Neuroepiteliais , Neurônios/metabolismo , Síndromes Neurotóxicas
8.
Int J Mol Sci ; 22(14)2021 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-34299375

RESUMO

A real-life environment during pregnancy involves multiple and simultaneous exposures to toxic chemicals. Perinatal exposures to toxic chemicals have been reported to exert an inhibitory effect on mouse neural development and behaviors. However, the effect of combined exposures of organophosphate and nicotine has not been previously reported. In this study, we investigated whether a combined exposure of diazinon and nicotine can have a synergistic effect. The effects of the combined chemical exposure on cell viability and neuronal differentiation were examined using mouse Sox1-GFP cells. Additionally, mice were maternally administered 0.18 mg/kg diazinon, a no adverse effect level (NOAEL) dose, combined with 0.4, 1, and 2 mg/kg nicotine. Mice offspring underwent behavior tests to assess locomotor, depressive, cognitive, and social behaviors. Morphological change in the brain was investigated with immunolocalization. We revealed that the combined exposure to diazinon and nicotine can have a synergistic adverse effect in vitro. In addition, the chemical-treated mouse offspring showed abnormalities in motor learning, compulsive-like behaviors, spatial learning, and social interaction patterns. Moreover, 0.18 mg/kg diazinon and 2 mg/kg nicotine co-exposure resulted in an increase in tyrosine hydroxylase (TH)-positive dopaminergic neurons. Thus, the findings suggest that perinatal co-exposure to nicotine and diazinon can result in abnormal neurodevelopment and behavior, even at low-level administration.


Assuntos
Comportamento Animal/efeitos dos fármacos , Encéfalo/efeitos dos fármacos , Diazinon/efeitos adversos , Nicotina/efeitos adversos , Animais , Células Cultivadas , Neurônios Dopaminérgicos/efeitos dos fármacos , Neurônios Dopaminérgicos/metabolismo , Feminino , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos C57BL , Gravidez , Efeitos Tardios da Exposição Pré-Natal/metabolismo , Comportamento Social , Aprendizagem Espacial/efeitos dos fármacos , Tirosina 3-Mono-Oxigenase/metabolismo
9.
Int J Mol Sci ; 22(5)2021 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-33807999

RESUMO

Inflammatory bowel diseases (IBDs) comprises a range of chronic inflammatory conditions of the intestinal tract. The incidence and prevalence of IBDs are increasing worldwide, but the precise etiology of these diseases is not completely understood. Calcium signaling plays a regulatory role in cellular proliferation. Nckx3, a potassium-dependent Na+/Ca2+ exchanger, is not only expressed in the brain but also in the aortic, uterine, and intestinal tissues, which contain abundant smooth muscle cells. This study investigated the role of Nckx3 in intestinal inflammation. Microarray analyses revealed the upregulation of the innate immune response-associated genes in the duodenum of Nckx3 knockout (KO) mice. The Nckx3 KO mice also showed an increase in IBD- and tumorigenesis-related genes. Using dextran sodium sulfate (DSS)-induced experimental colitis mice models, the Nckx3 KO mice showed severe colitis. Furthermore, the pathways involving p53 and NF-κB signaling were significantly upregulated by the absence of Nckx3. Overall, Nckx3 plays a critical role in the innate immune and immune response and may be central to the pathogenesis of IBD.


Assuntos
Colite/metabolismo , Doenças Inflamatórias Intestinais/metabolismo , NF-kappa B/metabolismo , Transdução de Sinais , Trocador de Sódio e Cálcio/genética , Proteína Supressora de Tumor p53/metabolismo , Animais , Colite/induzido quimicamente , Colite/genética , Sulfato de Dextrana/toxicidade , Modelos Animais de Doenças , Doenças Inflamatórias Intestinais/induzido quimicamente , Doenças Inflamatórias Intestinais/genética , Camundongos , Camundongos Knockout , NF-kappa B/genética , Trocador de Sódio e Cálcio/metabolismo , Proteína Supressora de Tumor p53/genética
10.
Mitochondrial DNA A DNA Mapp Seq Anal ; 28(2): 216-217, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-26710936

RESUMO

We obtained the complete mitochondrial genome of the Ussuri white-toothed shrew Crocidura lasiura (Insectivora, Soricidae) at 17 362 base pairs (bp) containing 13 protein-coding genes, two ribosomal RNAs, 22 transfer RNAs, and a non-coding control region. Its gene order is identical to that of other vertebrates. Several repeat elements were identified in the non-coding control region (D-loop). Phylogenetic tree using mt protein-coding gene sequences showed that C. lasiura was closely related to C. attenuata. The reports of mt genome sequences of Crocidura were not enough to study phylogenetic relationships in genome levels. However, this report may help us to understand the phylogenetic relationships and evolutionary history of Crocidura.


Assuntos
Genoma Mitocondrial , Musaranhos/genética , Animais , DNA Mitocondrial/genética , Proteínas Mitocondriais/genética , Filogenia , RNA Ribossômico/genética , RNA de Transferência/genética
11.
Mitochondrial DNA A DNA Mapp Seq Anal ; 28(2): 267-268, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-26714246

RESUMO

The complete mitochondrial genome of the Far Eastern Myotis, Myotis bombinus (Chiroptera, Vespertilionidae) is determined in this study. It is 17 128 base pairs in length with 13 protein-coding genes, 2 ribosomal RNAs, 22 transfer RNAs, and a non-coding control region. Its gene order is identical to that of other typical vertebrates. There are two tandem repeat sequences in the non-coding control region. Each repeat sequences contains 5 copies of 81 nucleotides and 42 copies of 6 nucleotides. Phylogenetic tree of mt 13 protein-coding gene sequences of 18 species in the family Vespertilionidae shows two distinct clades. Clade I consists of Myotis and Murina, while Clade II contains all other species analyzed.


Assuntos
Quirópteros/genética , Genoma Mitocondrial , Animais , Ordem dos Genes , Proteínas Mitocondriais/genética , Filogenia , RNA Ribossômico/genética , RNA de Transferência/genética
12.
Int J Mol Med ; 36(4): 1173-9, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26260034

RESUMO

Heat shock factor 2 (HSF2) is one of the most important regulators affecting stress mechanisms, and is frequently amplified in the ubiquitin proteasome pathway. Despite its significance, the mechanisms which regulate HSF2 expression remain unclear. In the present study, we describe the existence of a negative autoregulatory mechanism of HSF2. Transfection assays demonstrated that HSF2 decreased endogenous HSF2 mRNA expression in human K562 erythroleukemia cells. Luciferase reporter assays revealed that HSF2 inhibited the activity of its own promoter in a dose-dependent manner and that the downstream region (-1.5 kb) relative to the transcription start site was responsible for this inhibitory effect. Furthermore, chromatin immunoprecipitation (ChIP) assat indicated that HSF2 is directly recruited onto its own promoter, which contains a putative heat shock element (HSE). Collectively, the findings of our studys suggest that HSF2 contributes to its own expression by forming a negative autoregulatory loop.


Assuntos
Proteínas de Choque Térmico/biossíntese , Elementos de Resposta/fisiologia , Fatores de Transcrição/biossíntese , Transcrição Gênica/fisiologia , Animais , Proteínas de Choque Térmico/genética , Humanos , Células K562 , Camundongos , Camundongos Knockout , Fatores de Transcrição/genética
14.
J Vis Exp ; (68)2012 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-23149977

RESUMO

Through the ectopic expression of four transcription factors, Oct4, Klf4, Sox2 and cMyc, human somatic cells can be converted to a pluripotent state, generating so-called induced pluripotent stem cells (iPSCs)(1-4). Patient-specific iPSCs lack the ethical concerns that surround embryonic stem cells (ESCs) and would bypass possible immune rejection. Thus, iPSCs have attracted considerable attention for disease modeling studies, the screening of pharmacological compounds, and regenerative therapies(5). We have shown the generation of transgene-free human iPSCs from patients with different lung diseases using a single excisable polycistronic lentiviral Stem Cell Cassette (STEMCCA) encoding the Yamanaka factors(6). These iPSC lines were generated from skin fibroblasts, the most common cell type used for reprogramming. Normally, obtaining fibroblasts requires a skin punch biopsy followed by expansion of the cells in culture for a few passages. Importantly, a number of groups have reported the reprogramming of human peripheral blood cells into iPSCs(7-9). In one study, a Tet inducible version of the STEMCCA vector was employed(9), which required the blood cells to be simultaneously infected with a constitutively active lentivirus encoding the reverse tetracycline transactivator. In contrast to fibroblasts, peripheral blood cells can be collected via minimally invasive procedures, greatly reducing the discomfort and distress of the patient. A simple and effective protocol for reprogramming blood cells using a constitutive single excisable vector may accelerate the application of iPSC technology by making it accessible to a broader research community. Furthermore, reprogramming of peripheral blood cells allows for the generation of iPSCs from individuals in which skin biopsies should be avoided (i.e. aberrant scarring) or due to pre-existing disease conditions preventing access to punch biopsies. Here we demonstrate a protocol for the generation of human iPSCs from peripheral blood mononuclear cells (PBMCs) using a single floxed-excisable lentiviral vector constitutively expressing the 4 factors. Freshly collected or thawed PBMCs are expanded for 9 days as described(10,11) in medium containing ascorbic acid, SCF, IGF-1, IL-3 and EPO before being transduced with the STEMCCA lentivirus. Cells are then plated onto MEFs and ESC-like colonies can be visualized two weeks after infection. Finally, selected clones are expanded and tested for the expression of the pluripotency markers SSEA-4, Tra-1-60 and Tra-1-81. This protocol is simple, robust and highly consistent, providing a reliable methodology for the generation of human iPSCs from readily accessible 4 ml of blood.


Assuntos
Lentivirus/genética , Leucócitos Mononucleares/fisiologia , Células-Tronco Pluripotentes/fisiologia , Antígenos de Superfície/biossíntese , Vetores Genéticos/genética , Humanos , Fator 4 Semelhante a Kruppel , Leucócitos Mononucleares/citologia , Leucócitos Mononucleares/metabolismo , Células-Tronco Pluripotentes/citologia , Células-Tronco Pluripotentes/metabolismo , Proteoglicanas/biossíntese , Antígenos Embrionários Estágio-Específicos/biossíntese , Transdução Genética
15.
Mol Reprod Dev ; 75(7): 1127-35, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18324672

RESUMO

In the present study, we investigated the effect of melatonin on the preimplantation development of porcine parthenogenetic and somatic cell nuclear transfer (SCNT) embryos. Parthenogenetic embryos were cultured in mNCSU-23 supplemented with various concentrations of melatonin for 7 days. The results revealed that 100 pM was the optimal concentration, which resulted in significantly increased cleavage and blastocyst formation rates. Additionally, 100 pM melatonin provided the highest increase in total cell number of blastocysts. Therefore, the subsequent experiments were performed with 100 pM melatonin. ROS level in 2-8 cell stage embryos in the presence or absence of melatonin was evaluated. Embryos cultured with melatonin showed significantly decreased ROS. Blastocysts cultured with melatonin for 7 days were analyzed by the TUNEL assay. It was observed that melatonin not only increased (P < 0.05) the total cell number but also decreased (P < 0.05) the rate of apoptotic nuclei. Blastocysts cultured with melatonin were assessed for the expression of apoptosis-related genes Bcl-xl and Bax, and of pluripotency marker gene Oct-4 by real-time quantitative PCR. Analysis of data showed that the expression of Bcl-xl was higher (1.7-fold) compared to the control while the expression of Bax was significantly decreased relative to the control (0.7-fold) (P < 0.05). Moreover, the expression of Oct-4 was 1.7-fold higher than the control. These results indicated that melatonin had beneficial effects on the development of porcine parthenogenetic embryos. Based on the findings of parthenogenetic embryos, we investigated the effect of melatonin on the development of porcine SCNT embryos. The results also demonstrated increased cleavage and blastocyst formation rates, and the total cell numbers in blastocysts were significantly higher when the embryos were cultured with melatonin. Therefore, these data suggested that melatonin may have important implications for improving porcine preimplantation SCNT embryo development.


Assuntos
Apoptose/efeitos dos fármacos , Blastocisto/fisiologia , Desenvolvimento Embrionário/efeitos dos fármacos , Melatonina/farmacologia , Partenogênese/fisiologia , Animais , Blastocisto/citologia , Blastocisto/efeitos dos fármacos , Feminino , Marcação In Situ das Extremidades Cortadas , Técnicas de Transferência Nuclear , Partenogênese/efeitos dos fármacos , Reação em Cadeia da Polimerase , Gravidez , Suínos
16.
Anim Reprod Sci ; 105(3-4): 438-50, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18276088

RESUMO

The restricted supply of oocytes in the domestic dog limits the development of reproductive biotechnologies in this species. Inter-species somatic cell nuclear transfer could be an alternative for cloning animals whose oocytes are difficult to obtain. In this study, the possibility of cloning dog embryos using pig oocytes was investigated by evaluating nuclear remodeling. Chromatin remodeling, assessed by premature chromosome condensation, pseudo-pronuclei formation, DNA methylation and histone acetylation, along with the developmental ability was compared between intra- and inter-species cloned embryos. The incidence of premature chromosome condensation was significantly higher in intra-species cloned embryos relative to inter-species cloned embryos (87.2% vs. 61.7%; P<0.05), but comparable pseudo-pronuclei formation was observed in both (85.3% vs. 75.8%). None of the inter-species cloned embryos developed beyond the 8-cell stage while 18.3% of intra-species cloned embryos developed to the blastocyst stage. The relative level of both DNA methylation and histone acetylation was similar between intra- and inter-species cloned embryos at all times examined. These results suggest that although partial chromatin remodeling occurs, further investigation is needed to be able to use pig oocytes as recipient oocytes in dog cloning.


Assuntos
Montagem e Desmontagem da Cromatina/fisiologia , Clonagem de Organismos/veterinária , Cães/embriologia , Desenvolvimento Embrionário/fisiologia , Histonas/metabolismo , Oócitos/fisiologia , Suínos/fisiologia , Acetilação , Animais , Núcleo Celular/genética , Núcleo Celular/fisiologia , Clonagem de Organismos/métodos , Metilação de DNA , Feminino , Imuno-Histoquímica/veterinária , Cariotipagem/veterinária , Técnicas de Transferência Nuclear/veterinária
17.
Anim Reprod Sci ; 106(1-2): 13-24, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17482776

RESUMO

Insulin-transferrin-selenium (ITS) together has been used in different in vitro maturation system to support in vitro maturation of oocytes. The present study was designed to evaluate the effects of ITS in defined (0.1% PVA) and porcine follicular fluid (10% pFF) supplemented IVM media on the developmental competence of porcine oocytes. Three combinations of ITS, 10 mg/L insulin (Ins), 5.5mg/L transferrin (Tf) and 5 microg/L selenium (Se), 20mg/L Ins, 11 mg/L Tf and 10 microg/L Se, and 30 mg/L Ins, 16.5 mg/L TF and 15 microg/L Se, were used. The data were analyzed by one-way ANOVA and Tukey was used as the post hoc test. Both in the defined and pFF supplemented media, higher concentration of intracellular glutathione was observed in presence of ITS (4.6-4.8, and 6.9-7.1 picomole/oocyte for defined and pFF groups, respectively) compared to the respective control (2.1 and 4.3 picomole/oocyte for defined and pFF group, respectively). ITS decreased polyspermy and increased male pronucleus formation in both the defined and pFF supplemented medium. There was no difference in different treatment groups. The highest frequency of blastocyst formation rate and number of cells in blastocyst following IVF and SCNT was observed in pFF+ITS group (p<0.05). In conclusion, ITS addition during IVM improved the developmental competence of porcine oocytes in both the defined and pFF supplemented groups. Thus, we recommended to supplement porcine IVM medium with 10 microg/mL insulin, 5.5 microg/mL transferrin and 5 microg/mL selenium.


Assuntos
Fertilização in vitro/veterinária , Líquido Folicular/fisiologia , Insulina/farmacologia , Técnicas de Transferência Nuclear/veterinária , Selênio/farmacologia , Suínos , Transferrina/farmacologia , Animais , Células Cultivadas , Meios de Cultura/química , Meios de Cultura/farmacologia , Técnicas de Cultura Embrionária/veterinária , Embrião de Mamíferos , Feminino , Fertilização in vitro/métodos , Líquido Folicular/química , Glutationa/análise , Masculino , Oogênese/efeitos dos fármacos , Gravidez , Taxa de Gravidez , Suínos/embriologia
18.
Reproduction ; 134(3): 405-14, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17709559

RESUMO

In an effort to improve the quality of in vitro produced porcine embryos, we investigated the effect of brain-derived neurotropic factor (BDNF), a neurotropin family member, on in vitro maturation (IVM) of porcine oocytes. The expression of BDNF and truncated isoforms of its receptor, tyrosine kinase B (TrkB), and p75 common neurotropin receptor was detected in both follicular cells and metaphase-I stage oocytes by RT-PCR. However, mRNA of full-length TrkB was not found in oocytes although it was detected in follicular cells. The expression pattern of BDNF and TrkB was confirmed by immunohistochemistry. Supplementation with BDNF (30 ng/ml) during IVM significantly (P < 0.05) increased the first polar body extrusion and glutathione levels in oocytes, whereas the effect of BDNF on nuclear maturation was diminished when gonadotropin and epidermal growth factor (EGF) were added to the culture media. However, treatment with BDNF (30 ng/ml) along with EGF (10 ng/ml) in the presence of gonadotropin significantly (P < 0.05) increased the developmental competence of oocytes to the blastocyst stage after both in vitro fertilization (IVF; 29.1% when compared with control, 15.6%) and somatic cell nuclear transfer (SCNT; 13.6% when compared with control, 3%). This appeared to reflect a stimulatory interaction between BDNF and EGF to enhance the cytoplasmic maturation of oocytes to support successful preimplantation development. In conclusion, BDNFenhanced nuclearand cytoplasmic maturation of oocytes by autocrine and/or paracrine signals. Also, when used together with EGF, BDNF increased the developmental potency of embryos after IVF and SCNT, demonstrating an improved in vitro production protocol for porcine oocytes.


Assuntos
Fator Neurotrófico Derivado do Encéfalo/farmacologia , Oócitos/metabolismo , Oogênese/efeitos dos fármacos , Transdução de Sinais/fisiologia , Suínos , Animais , Fator Neurotrófico Derivado do Encéfalo/análise , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Células Cultivadas , Técnicas de Cultura Embrionária , Desenvolvimento Embrionário , Fator de Crescimento Epidérmico/farmacologia , Feminino , Fertilização in vitro/veterinária , Gonadotropinas Hipofisárias/farmacologia , Imuno-Histoquímica , Metáfase , Oócitos/citologia , RNA Mensageiro/análise , Reação em Cadeia da Polimerase Via Transcriptase Reversa
19.
Anim Reprod Sci ; 100(1-2): 107-17, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16860500

RESUMO

The susceptibility of embryos to reactive oxygen species (ROS) varies in different stages of embryo development. The present study evaluated temporal effects of alpha-tocopherol and L-ascorbic acid on the porcine embryo development, and investigated whether a single or twice supplements of these two antioxidants at a divided concentrations favors the embryo development. In order to determine temporal effects of alpha-tocopherol and/or L-ascorbic acid, 100 microM alpha-tocopherol or 200 microM L-ascorbic acid were supplemented to the North Carolina State University (NCSU)-23 embryo culture media at 0, 48, 96 and 120 h of culture. In another set of experiments, the concentration was divided into two equal halves, i.e., 50 microM alpha-tocopherol and 100 microM L-ascorbic acid, and supplemented twice at 0 and 48, 0 and 96, or 48 and 96 h of culture. Supplementing culture media with 100 microM alpha-tocopherol for the entire culture period of 168 h or starting from the 48 h of culture yielded higher blastocyst percentage compared with the control or starting from the 96 or 120 h of culture. L-Ascorbic acid (200 microM) alone or together with alpha-tocopherol (100 microM) with a single supplement did not affect the frequency of blastocyst formation or number of cells in blastocyst. L-ascorbic acid with a divided supplements yielded higher blastocyst percentage compared with the control. No synergistic effect was observed on embryo development at a single supplement of these antioxidants. Although, at divided supplements higher blastocyst percentage was observed compared with control group, no further beneficial effect was observed compared with alpha-tocopherol or L-ascorbic acid alone. Our results demonstrated that the embryotrophic effects of alpha-tocopherol and/or L-ascorbic acid, in terms of frequency of blastocyst formation and number of cells in blastocyst, depends on the concentration and supplementation timing.


Assuntos
Ácido Ascórbico/farmacologia , Embrião de Mamíferos/efeitos dos fármacos , Fertilização in vitro/veterinária , Suínos/embriologia , alfa-Tocoferol/farmacologia , Animais , Antioxidantes/administração & dosagem , Antioxidantes/farmacologia , Ácido Ascórbico/administração & dosagem , Esquema de Medicação , Embrião de Mamíferos/fisiologia , Feminino , Fatores de Tempo , alfa-Tocoferol/administração & dosagem
20.
Biochem Biophys Res Commun ; 348(4): 1419-28, 2006 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-16920069

RESUMO

Xenotransplantation is a rapidly expanding field of research and cloned miniature pigs have been considered as a model animal for it. However, the efficiency of somatic cell nuclear transfer (SCNT) is extremely low, with most clones resulting in early lethality and several kinds of aberrant development. A possible explanation for the developmental failure of SCNT embryos is insufficient reprogramming of the somatic cell nucleus by the oocyte. In order to test this, we analyzed the reprogramming capacity of differentiated fibroblast cell nuclei and embryonic germ cell nuclei with Oct-4 and Oct-4 related genes (Ndp5211, Dppa2, Dppa3, and Dppa5), which are important for embryonic development, Hand1 and GATA-4, which are important for placental development, as molecular markers using RT-PCR. The Oct-4 expression level was significantly lower (P<0.05) in cloned hatched blastocysts derived from fibroblasts and many of fibroblast-derived clones failed to reactivate at least one of the tested genes, while most of the germ cell clones and control embryos correctly expressed these genes. In conclusion, our results suggest that the reprogramming of fibroblast-derived cloned embryos is highly aberrant and this improper reprogramming could be one reason of the early lethality and post-implantation anomalies of somatic cell-derived clones.


Assuntos
Clonagem de Organismos , Técnicas de Transferência Nuclear , Fator 3 de Transcrição de Octâmero/metabolismo , Porco Miniatura/embriologia , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Núcleo Celular/genética , Células Cultivadas , Transferência Embrionária , Embrião de Mamíferos/metabolismo , Fertilização in vitro , Feto/metabolismo , Fibroblastos/metabolismo , Fator de Transcrição GATA4/genética , Fator de Transcrição GATA4/metabolismo , Expressão Gênica , Células Germinativas/metabolismo , Fator 3 de Transcrição de Octâmero/genética , RNA Mensageiro/metabolismo , Suínos , Porco Miniatura/genética , Porco Miniatura/metabolismo , Distribuição Tecidual
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA