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1.
Curr Mol Med ; 2023 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-37921189

RESUMO

BACKGROUND: USPs are a family of enzymes that regulate protein degradation, and their dysregulation has been implicated in the development and progression of cancer. AIMS: This study aimed to determine whether ubiquitin-specific proteases 3 (USP3) could be a potential target for therapy in hepatocellular carcinoma (HCC), particularly in resistant HCC. This study systematically investigated the role of USP3 in HCC, with a focus on chemo-resistant HCC cells. METHODS: The level of USP3 from clinical samples was measured using an ELISA assay. Cell proliferation, apoptosis, migration, and anchorage-independent colony formation assays were performed. Transfection was performed to knock down USP3 expression and measure ß-catenin activity, and real-time PCR was used to measure levels of MYC and CYCLIN D1 genes. RESULTS: USP3 protein was upregulated in HCC tissues, but its upregulation was not associated with clinicopathology. USP3 knockdown had a similar inhibitory effect on growth in both sensitive and resistant HCC cells, did not affect migration, and induced apoptosis in sensitive but not resistant HCC cells. Furthermore, USP3 knockdown was more effective in suppressing anchorage-independent colony formation in chemoresistant HCC cells compared to their chemo-sensitive counterparts. Pearson correlation coefficient analysis revealed a strong positive correlation between USP3 and CTNNB1, and consistently, USP3 knockdown reduced the levels and activities of ß-catenin in HCC cells. Using a Wnt activator (lithium) in rescue studies significantly reversed the inhibitory effects of USP3 knockdown. CONCLUSION: The findings suggest that inhibiting USP3 is an effective strategy against cancer stem cells and chemo-resistant HCC cells.

2.
Am J Transl Res ; 13(4): 3658-3665, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34017548

RESUMO

OBJECTIVE: The purpose of this study is to analyze the influencing factors of postoperative pain in patients presenting with emergency orthopedic trauma, and to determine the effect of high-quality nursing on pain. METHODS: In this prospective study, 78 emergency orthopedic trauma patients were randomized into the research group for high-quality nursing and the control group for routine emergency nursing. The two groups were compared with respect to pain degree, pain resolution time, related clinical indexes, pre- and post-treatment joint range of motion (ROM) and psychological state, as well as nursing satisfaction and complications. Univariate analysis and Logistic regression were carried out to analyze the influencing factors of pain following fractures. RESULTS: Compared with before operation (at baseline), the visual analogue scale (VAS) scores decreased gradually from 1 to 7 days postoperatively in both groups, and were lower in the research group than in the control group in the same time period (all P<0.05). Logistic regression analysis revealed that male, anxiety and/or depression as well as general family support were the major factors affecting postoperative pain in patients with traumatic fractures (P<0.05). Patients in the research group showed significantly less pain resolution time and evidently shorter time of hospitalization and fracture healing than the control group (all P<0.01). Compared with the baseline, ROM scores increased significantly in both groups after intervention, and were higher in the research group than in the control group; Hamilton anxiety (HAMA) and Hamilton depression (HAMD) scores reduced remarkably in the two series, and were even lower in the research group (all P<0.05). In comparison with the control group, the nursing satisfaction was higher and the incidence of complications was lower in the research group (both P<0.05). CONCLUSIONS: Gender, psychological state and family supportive attitudes have certain effects on postoperative pain degree of emergency orthopedic trauma patients. High-quality nursing can relieve postoperative pain degree and adverse psychological state of patients, with fewer complications, higher satisfaction and shorter hospitalization time.

3.
Spectrochim Acta A Mol Biomol Spectrosc ; 199: 202-208, 2018 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-29605784

RESUMO

A novel biphenyl-derived salicylhydrazone Schiff base (BSS) fluorescent probes for highly sensitive and selective identification of Cu2+ has been synthesized. In addition, the recognition has been proved experimentally. The results indicated that the complex forms a 1:1 complex with Cu2+ shows fluorescent quenching. Furthermore, the detection limit of 1.54×10-8M. More interesting, the probe BSS not only have a good biocompatibility in living cells, but also the sense behavior of Cu2+ in the cell nucleus.


Assuntos
Compostos de Bifenilo/química , Cobre/análise , Corantes Fluorescentes/química , Hidrazonas/química , Salicilatos/química , Bases de Schiff/química , Células HeLa , Humanos , Limite de Detecção , Espectrometria de Fluorescência
4.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-497430

RESUMO

With the arrival of SoloMo era and the change of users need, the passive service has changed to active service in libraries in order to increase the use of their resources. After the SoloMo concept was described, the bar-riers in users of medical libraries were investigated with questionnaires, the strategies for SoloMo innovative service and change of traditional service patterns in medical libraries were elaborated in order to provide personal service for the users at anytime and anywhere.

5.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-495081

RESUMO

Descibed in this paper are the problems in WeChat public platform construction in academic libraries of traditional Chinese medicine, including low litilization, ordinary columns, indistinct charaterized service, non-spe-cific recommendation of resources , poor charaterized knowledge interaction , and poor popularization , with measures proposed for their solution hoping that they would play an active role in promoting WeChat public platform construc-tion.

6.
Guang Pu Xue Yu Guang Pu Fen Xi ; 30(11): 3161-5, 2010 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-21284205

RESUMO

In modern dynamics system, the radiant temperature of the flame, which caused by the transient plasma stimulated by high-energy-level electromagnetism field, takes an important role in the description of the flying object's status as well as cauterization of the trajectory. Due to its extremely high temperature and transient process, the radiant temperature of the flame can hardly be measured through contracted ways, either static ways such as traditional pyrophotometer or CCD arrays. In the present paper, the authors bring forward a novel pyrophotometer based on classical theory of Planck's law (blackbody radiation law) and multi-channel spectrums radiation method. With this new type pyrophotometer, any spectrum can be selected out from the wavelength of 300 to 860 nm within 2 ns. Also, the application of high-definition diffraction grating and fibers can'ensure the accuracy of selected spectrum. The results through a serial of experiments by using this theory as well as high-speed photodetector indicate that this method is valid and accurate for the measurement of the object's surface's radiant temperature.

7.
Cell Tissue Res ; 327(1): 55-66, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16951941

RESUMO

An efficient co-culture system, especially with oviductal or uterine epithelial cells, is important not only for the production of high quality embryos, but also for the study of the molecular dialogue between embryos and their maternal environment. Although mouse embryos have been co-cultured successfully with oviductal epithelial cells (OECs) from several species, studies on the effects of species and functionality of OECs are few. Reports concerning the necessity of direct contact between the embryo and OECs and about the culture of mouse embryos in medium conditioned with heterologous OECs have been controversial. In this study, pronuclear embryos from Kunming mice, characterized by an obvious two-cell block in vitro, were co-cultured with mouse, goat, and chick OECs. The functionality of OECs was determined by analyzing the cell cycle, apoptosis, the numbers of mitochondria and cilia, and the ability both to support embryonic development and to remove hypoxanthine from the culture medium. The necessity of direct contact between OECs and embryos was studied by repeated renewal of culture medium with fresh conditioned medium, the culture of embryos in plastic wells connected by tunnels to wells with OEC monolayers, and the co-culture of embryos separated from OECs by a filter. Both goat and chick OECs supported mouse embryonic development, but their embryotrophic lifespan was shorter than that of the mouse OECs. Whereas media conditioned with mouse OECs supported mouse embryonic development satisfactorily, medium conditioned with goat OECs supported little development. Immediate dialogue between heterologous OECs and embryos was essential for efficient co-culture, whereas direct contact between the two cell types was not; neither dialogue nor contact was needed between isologous OECs and embryos. Embryotrophic activity and the ability to remove hypoxanthine from conditioned medium declined with time after confluence and number of passages of OECs, mainly because of apoptosis and dedifferentiation. Thus, the species and functionality of OECs have profound effects on their molecular dialogue with co-cultured embryos, and efficient co-culture depends upon both positive and negative conditioning.


Assuntos
Embrião de Mamíferos/citologia , Desenvolvimento Embrionário/fisiologia , Células Epiteliais/citologia , Oviductos/citologia , Animais , Apoptose/efeitos dos fármacos , Comunicação Celular/efeitos dos fármacos , Contagem de Células , Técnicas de Cocultura , Meios de Cultivo Condicionados/farmacologia , Embrião de Mamíferos/efeitos dos fármacos , Embrião de Mamíferos/metabolismo , Desenvolvimento Embrionário/efeitos dos fármacos , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Feminino , Cabras , Camundongos , Microscopia Confocal , Mitocôndrias/ultraestrutura , Oviductos/efeitos dos fármacos , Oviductos/metabolismo , Especificidade da Espécie
8.
Mol Reprod Dev ; 74(4): 468-77, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16998797

RESUMO

To achieve the best and reproducible results of experiments, effects of delayed excision of oviducts/ovaries on mouse ovarian/ovulated oocytes and embryos have been studied. Oviducts/ovaries were excised at different times after death of mice and effects of the postmortem interval on ovarian/ovulated oocytes and embryos were analyzed. When oviduct excision was delayed 10 min, many ovulated oocytes lysed or underwent in vitro spontaneous activation, and this postmortem effect aggravated with the extension of postmortem interval and oocyte aging. Oocytes from different mouse strains responded differently to delayed oviduct removal. Delayed oviduct excision did not cause lysis of zygotes or embryos but compromised their developmental potential. When ovaries were excised at 30 min after death, percentages of atretic follicles increased while blastocyst cell number declined significantly after oocyte maturation in vitro. Preservation of oviducts in vitro, in intact or opened abdomen at different temperatures and histological analysis of oviducts from different treatments suggested that toxic substance(s) were secreted from the dying oviducts which induced oocyte lysis and spontaneous activation and both this effect itself and the sensitivity of oocytes to this effect was temperature dependent. It is concluded that a short delay of oviduct/ovary removal had marked detrimental effects on oocytes and embryos. This must be taken into account in experiments using oocytes or embryos from slaughtered animals. The data may also be important for estimation of the time of death in forensic medicine and for rescue of oocytes from deceased valuable or endangered mammals.


Assuntos
Blastocisto/citologia , Tubas Uterinas/citologia , Oócitos/citologia , Ovário/citologia , Mudanças Depois da Morte , Manejo de Espécimes/efeitos adversos , Animais , Desenvolvimento Embrionário , Feminino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos , Gravidez , Fatores de Tempo
9.
J Reprod Dev ; 52(3): 373-82, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16518081

RESUMO

Methods for cell cycle synchronization of mouse fetal fibroblast cells (MFFCs) were first selected and optimized. When MFFCs were cooled at 5 C for different periods of time, the highest percentage of cells at the G0/G1 phase (75.4+/-2.9%), with 3.5+/-0.3% of apoptotic cells, was achieved after 5 h of treatment. Extended cooling increased the number of apoptotic cells significantly. When MFFCs were treated with different concentrations of roscovitine (ROS) for different periods of time, the highest percentage of G0/G1 cells (83.5+/-1.8%), with 9.2+/-0.6% apoptotic cells, was obtained after exposure to 10 microM ROS for 24 h. When the cells were cooled at 5 C for 5 h followed by incubation in 10 microM ROS for 12 h, 83.6+/-1.9% were synchronized at the G0/G1 stage, with 3.6% undergoing apoptosis. Cell cycle progression was then observed after release of the MFFCs from different synchronization blocks. The highest percentages of S and G2/M cells (81% and 75%) were achieved at 12 and 20 h, respectively, after release of the MFFCs from the cooling plus ROS treatment, and these percentages were significantly higher than those obtained after release from the cooling or ROS alone blocks. Finally, MFFCs were transfected with pEGFP-N1 plasmid at the peak of the G0/G1, S, and G2/M phases, respectively, after release from the different blocks and both the transient and stable transfection efficiencies were determined. The GFP gene expression was greatly enhanced when transfection was performed at the time when most cells were at the G2/M stage after release from cooling, ROS alone, and cooling plus ROS treatments. Statistical analysis revealed a close correlation between the rate of G2/M cells and the transient and stable GFP gene expression efficiencies. Together, the results indicated that (a) the best protocol for cell cycle synchronization of MFFCs was a 5-h cooling at 5 C followed by incubation in 10 microM ROS for 12 h which produced both a high rate of synchronization in the G0/G1 phase with acceptable apoptosis and a high rate of G2/M cells after release; and (b) that the cell cycle status had marked effects on the efficiency of liposome-mediated transfection in MFFCs, with the highest transfection efficiency obtained in cells at the G2/M stage.


Assuntos
Ciclo Celular , Fibroblastos/citologia , Fibroblastos/metabolismo , Transfecção/métodos , Animais , Apoptose , Células Cultivadas , Feto/citologia , Proteínas de Fluorescência Verde/genética , Interfase , Lipossomos , Camundongos , Purinas/farmacologia , Roscovitina , Temperatura , Transfecção/normas
10.
Mol Reprod Dev ; 73(7): 834-40, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16572465

RESUMO

Dairy goats are ideal for the transgenic production of therapeutic recombinant proteins. The use of recombinant somatic cell lines for nuclear transfer (NT) allows the introduction of genes by transfection, increases the efficiency of transgenic animal production to 100%, and overcomes the problem of founder mosaicism. Although viable animals have been cloned via NT from somatic cells of 11 species, the efficiency has been extremely low. Both blastomere and somatic cell NT increased fetal loss and perinatal morbidity/mortality in cattle and sheep, but fetal loss and perinatal mortality appear to be relatively low in goats. In this study, we produced cloned goats by NT from cumulus cells and long-term cultured fetal fibroblast cells (FFCs) to abattoir-derived oocytes. NT embryos were constructed from electrofusion of cumulus cells (CCs), FFCs, or skin fibroblast cells (SFCs) with cytoplasts prepared from abattoir-derived ovaries. The NT embryos were activated with an optimized activating protocol (1 min exposure to 2.5 microM ionomycin followed by 2 hr incubation in 2mM 6-DMAP). Two viable cloned kids from CCs and one from long-term cultured FFCs (at passage 20-25) were born. Microsatellite analysis of 10 markers confirmed that all cloned offspring were derived from corresponding donor cells. To our knowledge, the production of cloned goat offspring using abattoir-derived oocytes receiving nuclei from CCs and long-term cultured FFCs has not been reported. The production of viable cloned animals after activation with reduced intensity of ionomycin and 6-DMAP treatment has also not been reported. Loss of cloned embryos was obvious after 45 and 90 days of pregnancy, and a lack of cotyledons, heart defects, and improperly closed abdominal wall were observed in the aborted fetuses and one cloned kid. The fusibility and in vitro developmental potential of embryos reconstructed from FFCs at passage 20-25 were significantly lower than those of embryos reconstructed from FFCs at passage 3-5, and the cloning efficiency of the long-term cultured cells was low (0.5%).


Assuntos
Clonagem de Organismos/métodos , Transferência Embrionária , Cabras , Oócitos , Matadouros , Aborto Animal , Animais , Células Cultivadas , Desenvolvimento Embrionário , Feminino , Fibroblastos/citologia , Doenças das Cabras , Cabras/genética , Técnicas de Transferência Nuclear , Oócitos/citologia , Folículo Ovariano/citologia , Gravidez
11.
Shi Yan Sheng Wu Xue Bao ; 38(5): 404-10, 2005 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-16363120

RESUMO

We studied the effects of the amount of liposome and plasmid, exposure time of cells to the liposome-plasmid complexes, number of cell passages and cell types on GFP gene transfection of mouse somatic cells. The maximal GFP transgene expression (30.7%) was achieved when mouse fetal fibroblast cells (MFFC) at 70%-90% confluence of passage 3 were exposed for 6 h to the complexes of 4 microg liposome (LipofectAMINE) and 0.3 microg plasmid (pEGFP-N1). Under these conditions, we compared the effect of the number (from primary to 15) of passages on the transfection efficiency of MFFC. The transfection efficiency of MFFC was 10.0%, 28.9% and 7.2% at the primary, 3rd and 15th passage, respectively, which indicated that the transfection efficiency decreased with passaging. When MFFC, mouse oviductal epithelial cells (MOEC) and mouse granulosa cells (MGC) were transfected at passage 3, the transfection efficiency was 27.8%, 13.7% and 14.2%, respectively, under the described transfection conditions. When the cell cycle stages of different cell types at transfection were examined, it was found that 17.2% of MFFC, 8.7% of MOEC and 9.9% of MGC were at M phases of the cell cycle. Examination of the cell cycle stages of MFFC at different passages showed that MFFC at the third passage had the highest percentage of M cells and the percentage decreased afterwards. This suggested that the transfection efficiency was correlated with the percentages of cells at M phase, and provided essential data for improvement of the transfection efficiency.


Assuntos
Lipossomos , Transfecção , Animais , Ciclo Celular , Células Cultivadas , Feminino , Citometria de Fluxo , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Camundongos , Microscopia de Contraste de Fase , Gravidez
12.
Theriogenology ; 64(5): 1142-57, 2005 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-16125558

RESUMO

Strontium has been successfully used to induce activation of mouse oocytes in nuclear transfer and other experiments, but the optimum treatment conditions have not been studied systematically. When cumulus-free oocytes were treated with 10mM SrCl(2) for 0.5-5h, activation rates (88.4+/-4.1 to 91.2+/-2.7%) did not differ (mean+/-S.E.; P>0.2), but rate of blastulation (57.3+/-3.5%) and cell number per blastocyst (45.0+/-2.4) were the highest after treatment for 2.5h. When treated with 1-20mM SrCl(2) for 2.5h, the activation rate and cell number per blastocyst were higher (P<0.02) after 10mM SrCl(2) treatment than other treatments. The best activation and development were obtained with Ca(2+)-free Sr(2+) medium, but the activation rate was low (37.7+/-1.6%) in Ca(2+)-containing medium. Activation rates were the same, regardless of the presence or absence of cytochalasin B (CB) in the activating medium, but the blastulation rate was higher (P<0.001) in the presence of CB. Only 70% of the cumulus-enclosed oocytes were activated and 10% blastulated after a 10 min exposure to 1.6mM SrCl(2), and many lysed, with increased intensity of Sr(2+) treatment. The presence of CB in SrCl(2) medium markedly reduced lysis of cumulus-enclosed oocytes. Media M16 and CZB did not differ when used as activating media. Only 10.5% of the oocytes collected 13 h post hCG were activated by Sr(2+) treatment alone, with 34% blastulating, but rates of activation and blastulation increased (P<0.001) to 94 and 60%, respectively, when they were further treated with 6-dimethylaminopurine (6-DMAP). The total and ICM cell numbers were less (P<0.001) in parthenotes than in the in vivo fertilized embryos. In conclusion, the concentration and duration of SrCl(2) treatment and the presence or absence of CB in activating medium and cumulus cells had marked effects on mouse oocyte activation and development. To obtain the best activation and development, cumulus-free oocytes collected 18 h post hCG should be treated for 2.5h with 10mM SrCl(2) in Ca(2+)-free medium supplemented with 5 microg/mL of CB.


Assuntos
Oócitos/fisiologia , Partenogênese/efeitos dos fármacos , Estrôncio/farmacologia , Adenina/administração & dosagem , Adenina/análogos & derivados , Animais , Blastocisto/citologia , Cálcio/farmacologia , Contagem de Células , Meios de Cultura , Citocalasina B/farmacologia , Relação Dose-Resposta a Droga , Técnicas de Cultura Embrionária , Feminino , Peptídeos e Proteínas de Sinalização Intracelular/farmacologia , Magnésio/farmacologia , Camundongos , Oócitos/efeitos dos fármacos
13.
Mol Reprod Dev ; 71(3): 380-8, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15806561

RESUMO

The protocol of ionomycin followed by 6-dimethylaminopurine (6-DMAP) is commonly used for activation of oocytes and reconstituted embryos. Since numerous abnormalities and impaired development were observed when oocytes were activated with 6-DMAP, this protocol needs optimization. Effects of concentration and treatment duration of both drugs on activation and development of goat oocytes were examined in this study. The best oocyte activation (87-95%), assessed by pronuclear formation, was obtained when oocytes matured in vitro for 27 hr were treated with 0.625-20 microM ionomycin for 1 min before 6-hr incubation in 2 mM 6-DMAP. Progressional reduction of time for 6-DMAP-exposure showed that the duration of 6-DMAP treatment can be reduced to 1 hr from the second up to the fourth hour after ionomycin, to produce activation rates greater than 85%. Activation rates of oocytes in vitro matured for 27, 30, and 33 hr were higher (P < 0.05) than that of oocytes matured for 24 hr when treated with ionomycin plus 1-hr (the third hour) 6-DMAP, but a 4-hr incubation in 6-DMAP enhanced activation of the 24-hr oocytes. Goat activated oocytes began pronuclear formation at 3 hr and completed it by 5-hr post ionomycin. An extended incubation in 6-DMAP (a) impaired the development of goat parthenotes, (b) quickened both the release from metaphase arrest and the pronuclear formation, and (c) inhibited the chromosome movement at anaphase II (A-II) and telophase II (T-II), leading to the formation of one pronucleus without extrusion of PB2. In conclusion, duration, concentration, and timing of ionomycin and 6-DMAP treatment had marked effects on goat oocyte activation, and to obtain better activation and development, goat oocytes matured in vitro for 27 hr should be activated by 1 min exposure to 2.5 microM ionomycin followed by 2 mM 6-DMAP treatment for the third hour.


Assuntos
Adenina/análogos & derivados , Ionomicina/farmacologia , Ionóforos/farmacologia , Meiose/efeitos dos fármacos , Oócitos/fisiologia , Inibidores de Proteínas Quinases/farmacologia , Animais , Células Cultivadas , Feminino , Cabras , Oócitos/citologia
14.
J Exp Zool A Comp Exp Biol ; 301(10): 837-43, 2004 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-15449342

RESUMO

To study the effect of post-treatment with 6-Dimethylaminopurine (6-DMAP) on oocyte activation and development, mouse oocytes collected at different times post human chorion gonadotropin (hCG) injection were incubated in 6-DMAP-containing Chatot-Ziomek-Bavister (CZB) medium for different periods after ethanol exposure, and activation and development were observed. When oocytes were cultured in 6-DMAP without prior ethanol exposure, the highest activation rate was only 40%. Incubation in 6-DMAP for 6 h following ethanol exposure significantly (P < 0.05) increased the activation rate in oocytes recovered 15 and 18 h post hCG, but this effect was not significant in the 21 h oocytes. When oocytes were incubated in 6-DMAP for 1 h at different time points after ethanol, a 6-DMAP susceptible temporal window was found to be located from the second to the fifth h in the 18 h oocytes and from the fourth to the fifth h in the 15 h oocytes, and within the window, the duration of 6-DMAP incubation can be reduced to 0.5 h with more than 80% activation. With the 13 h oocytes, however, 6-DMAP-incubation can only be shortened to 3 h and no specific temporal window was identified. Oocytes that were incubated in 6-DMAP for 1 or 2 h after ethanol exposure developed to morula/blastocyst stages at significantly (P < 0.05) higher rates than those incubated in 6-DMAP for 6 h. Our results suggested that (i) long duration of 6-DMAP incubation impaired the development of mouse parthenogenotes; (ii) the effect of 6-DMAP alone was limited without prior ethanol exposure; (iii) the egg age affected both the timing of 6-DMAP susceptibility and the duration of exposure required to obtain a maximal activating effect; (iv) the most effective activating protocols varied for oocytes of different ages.


Assuntos
Adenina/análogos & derivados , Adenina/farmacologia , Etanol/farmacologia , Oócitos/efeitos dos fármacos , Análise de Variância , Animais , Meios de Cultura , Relação Dose-Resposta a Droga , Camundongos , Camundongos Endogâmicos , Oócitos/metabolismo , Fatores de Tempo
15.
Mol Reprod Dev ; 69(2): 228-34, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15293225

RESUMO

Changes in germinal vesicle (GV) chromatin configurations during growth and maturation of porcine oocytes were studied using a new method that allows a clearer visualization of both nucleolus and chromatin after Hoechst staining. The GV chromatin of porcine oocytes was classified into five configurations, based on the degree of chromatin condensation, and on nucleolus and nuclear membrane disappearance. While the GV1 to 4 configurations were similar to those reported by previous studies, the GV0 configuration was distinct by the diffuse, filamentous pattern of chromatin in the whole nuclear area. Most of the oocytes were at the GV0 stage in the <1 and 1-1.9 mm follicles, but the GV0 pattern disappeared completely in the 2-2.9 and 3-6 mm follicles. As follicles grew, the number of oocytes with GV1 configurations increased and reached a maximum in the preovulatory follicles 4 hr post-hCG injection. During maturation in vivo, the number of GV1 oocytes decreased while oocytes undergoing GVBD increased. The percentage of oocytes with GV3 and GV4 configurations was constant during oocyte growth except at the 2-2.9 mm follicle stage, but these configurations disappeared completely after hCG injection. On the contrary, the in vitro maturing oocytes showed a large proportion of GV3 and GV4 configurations. There was no significant difference in distribution of chromatin configurations between the nonatretic and atretic follicles, and between oocytes with more than two layers of cumulus cells and those with less than one layer or no cumulus cells. Overall, our results suggested that (i) the GV0 configuration in porcine oocytes corresponded to the "nonsurrounded nucleolus" pattern in mice and other species; (ii) all the oocytes were synchronized at the GV1 stage before GVBD and this pattern might, therefore, represent a nonatretic state; (iii) the GV3 and GV4 configurations might represent stages toward atresia, or transient events prior to GVBD that could be switched toward either ovulation or atresia, depending upon circumstances; (iv) the in vitro systems currently used were not favorable for oocytes to switch toward ovulation (or final maturation); (v) the number of cumulus cells was not correlated with the chromatin configuration of oocytes, indicating that the beneficial effect of cumulus cells on oocyte maturation and development may simply be attributed to their presence during in vitro culture.


Assuntos
Cromatina/ultraestrutura , Oócitos/citologia , Folículo Ovariano/citologia , Animais , Nucléolo Celular/ultraestrutura , Feminino , Técnicas In Vitro , Oócitos/ultraestrutura , Folículo Ovariano/ultraestrutura , Suínos
16.
Shi Yan Sheng Wu Xue Bao ; 37(1): 9-14, 2004 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-15133892

RESUMO

The meiotic progression of goat oocytes from follicles of different diameters was investigated in this study. The results were summarized as follows: (1) The in vitro meiotic maturation capacity was different among oocytes from follicles of different diameters. And thus oocytes from < or = 0.5 mm follicles were unable to resume meiosis; oocytes from 0.8-1.2 mm follicles were capable to resume meiosis, but could develop only to MI stage (60% at 24 h); oocytes from 1.5-5 mm follicles had acquired full-meiotic maturation capacity and 91% of them developed to M II stage at 24 h of culture. (2) The percentage of oocytes with intact-germinal vesicles from 1.5-5 mm follicles decreased significantly during 2-8 h of in vitro maturation and the decrease was even more rapid during 4-6 h of culture (from 60% to 19%, p < 0.0005). The percentage of oocytes at M I-stage increased from 24% to 61% during 6-12 h of in vitro maturation, and it then decreased. By 24 h of culture, only 2% oocytes remained at M I-stage. Twenty one percent of the oocytes in this group developed to M II-stage at 16 h of culture, and by 24 h of culture, 91% were at M II-stage. (3) Statistic analysis of the meiotic progression (the duration of each cell cycle stage) of oocytes from 1.5-5 mm follicles showed that GV stage lasted from 0 to 3 h of culture, prometaphase-I stage was from 3.0 to 7.0 h, metaphase-I stage was from 7.0 to 14.6 h, anaphase-I/telophase-I was from 14.6 to 18.4 h and metaphase-II stage lasted from 18.4 to 24 h. (4) Whether the oocytes capable of GVBD and entrance of M I developed to M II, the timing of meiotic progression prior to M I was similar. In summary, our results provided necessary data for studies on the mechanisms and control of meiosis in mammalian oocytes.


Assuntos
Meiose/fisiologia , Oócitos/fisiologia , Folículo Ovariano/anatomia & histologia , Animais , Células Cultivadas , Feminino , Cabras , Metáfase , Oócitos/citologia
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