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1.
Background: Integrins are heterodimeric glycoprotein receptors that regulate the interaction of cells with extracellular matrix and may have a critical role in implantation. The aim of this study was to investigate the effect of ovulation induction on the expression of α4, αv, β1, and β3 integrins in mouse blastocyst at the time of implantation. Methods: The ovarian stimulated and non-stimulated pregnant mice were sacrificed on the morning of 5th day of pregnancy. The blastocysts were collected, and the expression of αv, α4, β1, and β3 integrins was examined using real-time RT-PCR and immunocytochemical techniques, then their ovarian hormones were analyzed at the same time. The implantation sites in uterine horns of other pregnant mice in both groups were determined under a stereomicroscope on the 7th day of pregnancy. Results: The results showed that the expression of αv, β1, and β3 integrins in both mRNA and protein levels was significantly lower in the ovarian stimulated group than the control group, and the maximum ratio of expression was belonged to β1 molecule (P>0.05). Conclusion: The implantation rate in superovulated mice was significantly lower than control mice. It was suggested that ovulation induction decreased the expression of αv, β1, and β3 integrins of mouse blastocysts. Key Words: Blastosyst, Integrins, Implantation  相似文献   

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3.
Background : Oocyte cryopreservation is one of the most important topics in the field of assisted reproductive technology to preserve women fertility, but relationship between cryopreservation and apoptosis is still a matter of debate. The present study was aimed to investigate the effects of vitrification on apoptosis in mouse oocytes by Cryotop method. Method: A total of 200 germinal vesicle (GV) and 200 metaphase II (MII) oocytes were obtained from ovaries and fallopian tubes of NMRI mice, respectively and divided into control and experimental groups. Oocytes in experimental group were vitrified by Cryotop using vitrification medium and were kept in liquid nitrogen for one month. The survival rate of oocytes was evaluated after 2 hour incubation time. Then, the oocyte apoptosis was evaluated by TUNEL technique and compared with those in control group. The data was compared statistically using SPSS software and chi-square test. Results: The survival rates of vitrified GV (93%) and MII oocytes (88%) showed a significant decrease compared with the control group (P<0.05), but there was no significant difference in survival rate of both vitrified oocyte groups. The incidence of apoptosis in vitrified and control GV oocytes showed no significant difference (13% vs. 7%), but the rate of apoptosis in vitrified MII oocytes increased significantly not only in comparison with MII control group (25% vs. 5%) but also with vitrified GV oocytes (P<0.05). Conclusion: The results indicate that vitrification increases apoptosis in mouse MII oocytes and apoptosis may play a role in MII oocyte injury after vitrification. Key Words: Vitrification, Apoptosis, Oocytes  相似文献   

4.
Background: The ovariectomized animals are good models to evaluate the effect of different steroid hormone treatments on implantation events and the pattern of integrin expression. Therefore, this study was performed to compare the expression of integrins and osteopontin (OPN) in correlation with pinopode development in ovariectomized mice endometrium which was subjected to steroid hormones. Methods: Ovariectomized mice were subjected to estrogen, progesterone and estrogen-progesterone hormones. Their uterine horns were evaluated for integrin expression by immunohistochemistry and real-time RT-PCR and for pinopode development by transmission and scanning electron microscopic studies. Results: No immunostaining for integrin and OPN molecules were detected in the endometrium of non-ovariectomized mice except in metestrus phase. The α4 and β1 integrin genes were expressed in all phases of estrous cycle. In ovariectomized mice, no reaction was detected in the endometrium of control, sham and estrogen-treated groups, but in both progesterone-treated groups, all examined genes were expressed. There was not any correlation between pinopodes and integrin expression in ovariectomized mice. Conclusion: The progesterone is more effective on endometrial integrin expression than estrogen and differences in the expression pattern of integrins reflect their important and different roles in embryo implantation. The pinopodes may have minor effect in mice implantation or have some delay in their expressions in ovariectomized mice which were subjected to exogenous hormones. Key Words: Endometrium, Estrogen, Integrin, Ovariectomized mice, Osteopontin (OPN)  相似文献   

5.
为了解茶树主要食叶类害虫灰茶尺蠖(EctropisgrisescensWarren)雌成虫的内外生殖器结构特征,通过解剖切片和显微观察的方法,明确了雌成虫内外生殖器主要由1对卵巢、1对侧输卵管、1根中输卵管、1个受精囊、附腺、产卵孔、交配囊及其附属结构、导精管、表皮突和肛突等组成。卵巢小管8根,左右对称;交配囊呈典型袋状结构,内有表面布满刺状突的心型交尾囊片,且囊片左右两侧16根刺状突呈对称分布;后表皮突较细长,似铲状。切片观察可知,卵巢管滋养细胞和卵母细胞交替排列,为典型的多滋式;产卵器内有发达的性腺等。掌握灰茶尺蠖雌成虫生殖器结构,对其卵巢发育级别划分、田间预测预报、近缘种的鉴定以及性信息素的研究等具有重要意义。  相似文献   

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7.
荔枝花芽分化分为诱导、发端和分化3个阶段。试验以早中熟品种‘妃子笑’和中熟品种‘桂味’为试材,对荔枝花芽分化不同物候阶段叶片净光合速率(Pn)、叶绿素指数(SPAD)、荧光参数和碳氮物质等生理指标的变化规律进行研究。结果表明：‘妃子笑’的成花进程早于‘桂味’品种,但2个品种在整个花芽分化期间的相关生理指标均呈相似变化趋势,Pn和SPAD在诱导期和抽穗期水平较低,“白点”期和花蕾期有所增加,而荧光参数恰好相反;荔枝成花期间,其可溶性总糖含量在“白点”期阶段水平最低,而淀粉和总氮含量呈相反趋势,在“白点”期达到最高值。可见,不同荔枝品种的光合特性与碳氮物质变化受其花芽分化的阶段性影响更大,而“白点”期是荔枝碳氮物质变化较为关键的转折点。  相似文献   

8.
The aim of this study was to investigate the role of Nitric Oxide (NO) in the atresia of ovarian follicles in an animal model. Twenty adult, female rats (90 days old with body weights of210 +/- 10 g in the beginning of the experiments) were divided into 4 groups of 5 each. They were treated twice daily from the subcutaneous route for 21 successive days with either of the following chemicals: nitroglycerine, L-arginine, L-NAME, or saline. On day 22, all animals were sacrificed. Ovaries were dissected out free of connected tissue and were fixed in formaline 10%. Later, paraffine blocks were prepared and serial sections were made by means of H and E routine staining method. Intact and atretic follicles were counted separately. In addition, damages were analyzed qualitatively from the points of view of appearance and morphologic changes. In the evaluation of ovarian follicular structures, different types of healthy as well as atretic follicles were observed. In most of atretic follicles, the oocytes were abnormally elongated and increnation of their outlines were obvious. There were numerous macrophages around and inside of the atretic follicles. Our investigation regarding the distribution of atretic follicles in the ovaries of test groups revealed that atretic follicles in the L-NAME treated group were increased in comparison to the control group. Conversely, however, in the arginine-treated group, the atretic follicles were reduced compared to the control animals. Treatment with nitroglycerine of the rats decreased the number of atretic follicles significantly (p < 0.05) in comparison to the control group. In conclusion, enhanced NO, either from endogenous or exogenous origins, prevents atresia phenomenon, while inhibition of NO exerts an opposite effect.  相似文献   

9.
为探究L-茶氨酸（L-theanine,LTA）对来曲唑诱导的多囊卵巢综合征（Polycystic ovarian syndrome,PCOS）大鼠临床症状的改善效果。将28只雌性SD大鼠按每组7只随机分为正常对照组、PCOS模型组、PCOS+低剂量LTA组和PCOS+高剂量LTA组。建模阶段,除正常对照组以生理盐水灌胃外,其余3组持续灌胃来曲唑28 d诱导PCOS模型。干预阶段,正常对照组和PCOS模型组以生理盐水持续灌胃,两个LTA干预组大鼠分别持续灌胃对应剂量LTA干预30 d。结果显示,与PCOS模型组相比,LTA干预组大鼠血清中睾酮（Testosterone,T）、黄体生成素（Luteinizing hormone,LH）、胰岛素（Insulin,INS）、甘油三酯（Triglyceride,TG）、总胆固醇（Total cholesterol,TC）、低密度脂蛋白（Low-density lipoprotein cholesterol,LDL-C）、脂多糖（Lipopolysaccharide,LPS）水平及胰岛素抵抗指数（HOMA-IR）均显著降低（P<0.05）,高密度脂蛋白（High-density lipoprotein cholesterol,HDL-C）水平均显著升高（P<0.05）,黄体生成素与卵泡刺激素的比值（LH/FSH）、空腹血糖（Fasting plasma glucose,FPG）和体重均有所下降（P>0.05）;低剂量LTA干预组大鼠血清雌二醇（Estradiol,E2）显著升高（P<0.05）;高剂量LTA干预组大鼠卵泡刺激素（Follicle stimulating hormone,FSH）显著升高（P<0.05）;LTA干预组大鼠的发情周期紊乱、卵巢组织多囊样病变较PCOS模型组均有一定程度的改善。结果表明,LTA干预能有效调节PCOS大鼠性激素分泌、恢复发情周期规律变化和改善其卵巢多囊样病变,同时显著改善PCOS大鼠胰岛素抵抗（Insulin resistance,IR）、血脂代谢紊乱并抑制异常水平的脂多糖（Lipopolysaccharide,LPS）分泌。  相似文献   

10.
Background: Cryopreservation of pre-antral follicles is a hopeful technique to preserve female fertility. The aim of the present study was to evaluate reactive oxygen species (ROS) and total antioxidant capacity (TAC) levels of mouse vitrified pre-antral follicles in the presence of alpha lipoic acid (ALA). Methods: Isolated pre-antral follicles (140–150 µm in diameter) were divided into vitrified–warmed and fresh groups. Each group was subjected to in vitro maturation with or without ALA for 12 days, followed by adding human chronic gonadotropin to induce ovulation. In vitro fertilization was performed to evaluate their developmental competence. In parallel, the amount of ROS and TAC were assessed after 0, 24, 48, 72, and 96 h of culture by 2'',7''-dichlorofluorescin assay and ferric reducing/antioxidant power assay, respectively. Results: The respective rates of survival, antrum formation, and metaphase II oocytes were significantly higher in ALA-supplemented groups compared to the groups not treated with ALA. TAC and ROS levels were significantly decreased and increased, respectively during the culture period up to 96 h in the absence of ALA in both vitrified and non-vitrified samples. However, with pretreatment of ALA, TAC levels were increased significantly and remained constant up to 96 h in vitrified-warmed pre-antral follicles, while ROS levels completely returned to the level of starting point after 96 h of culture in the presence of ALA. Conclusion: Pretreatment of ALA positively influences development of pre-antral follicles in vitrified and non-vitrified samples through increasing follicular TAC level and decreasing ROS levels. Key Words: Vitrification, Pre-antral follicle, Alpha lipoic acid (ALA), Reactive oxygen species (ROS), Total antioxidant capacity (TAC)  相似文献   

11.
Background: In this study, we evaluated the incidence of apoptosis at the ultrastructural levels and expression of some apoptosis-related genes in vitrified human ovarian tissue just after warming. Methods: Human ovarian tissue biopsies from 23 women after caesarean section were transported to the laboratory within 2 hours, and then they were cut into small pieces. Some pieces were vitrified and warmed and the other samples were considered as control. Apoptosis was assessed by a transmission electron microscope and also by molecular analysis of pro-apoptotic (Fas, FasL, Bax, p53, caspase8, and caspase3) and antiapoptotic (Bcl-2 and BIRC5) genem RNA levels using real-time RT-PCR before and after vitrification. Results: No sign of apoptosis was shown ultrastructurally in vitrified samples. The level of FasL, Bcl-2, Bax, p53, and caspase3 mRNA and Bax:Bcl-2 ratio were similar in non-vitrified and vitrified groups; however, the expression of Fas and caspase8 genes was higher and BIRC5 was lower in vitrified samples compared to non-vitrified group (P<0.05). Conclusion: The fine structure of human vitrified ovarian tissue was well preserved; moreover, vitrification was shown to affect the expression of some apoptosis-related genes. However, additional study is needed to confirm this observation.Key Words: Vitrification, Apoptosis, Gene expression, Ovary, Humans  相似文献   

12.
Background: Amiodarone is a drug that is used for treatment of cardiac arrhythmia after cardiac ischemia. This drug as beta blocker decreases arrhythmia rate but it has many side effects on different tissues. Since there are rare reports about changes of lacrimal glands, this research has been carried out to study the morphological and ultrastructural changes of lacrimal gland cells after amiodarone administration. Methods: Male rabbits (n = 14) were divided into control and experimental groups. Experimental group were intra peritoneally injected with a daily single dose of 80 mg/kg amiodarone for two weeks. The control group only received normal saline. At the end of the injection period, the two groups were anesthetized and perfused with Karnovsky's fixative. The lacrimal glands were removed, fixed and then prepared for light and electron microscopic studies. Quantitative studies on lacrimal gland cell micrographs were performed by point counting method. The results were statistically compared between the two groups. Results: Light microscopic observation showed many secretory granules in the cytoplasm of the lacrimal gland cells, which were also seen in the lumen of acini. Ultrastructure study of these cells showed the presence of inclusions in their cytoplasm with homogenous and dense structure. In quantitative analysis, the volume fractions (Vv) of mitochondria and nucleus to the cell showed no differences between the two groups but the Vv of euchromatin to the nucleus was different (P<0.05 ). Conclusion: The presented results show adverse effects of amiodarone on rabbit lacrimal gland cells.  相似文献   

13.
为研究甘蓝型油菜HMG（high mobility group）基因家族的起源、进化和功能,利用生物信息学方法对甘蓝型油菜和其近缘物种HMG基因家族进行鉴定,并对其进化、基因结构、组织表达、直系旁系同源基因进行系统分析。在甘蓝型油菜中鉴定到45个HMG家族成员,并根据进化树和基因结构将其分成5组。染色体定位发现,19条染色体中有18条染色体有HMG基因,说明该家族基因分布较广泛。在甘蓝型油菜与甘蓝、白菜和拟南芥分别鉴定到47、45和26个直系同源基因对。在甘蓝型油菜中鉴定到28个旁系同源基因对,而在其它3个物种中则比较少,这可能与甘蓝型油菜的多次基因组加倍有关。对45个甘蓝型油菜BnHMG基因在根和叶中的表达模式进行分析,结果显示,大多数基因在根和叶中均有表达,且呈现出不同的表达模式。  相似文献   

14.
ABSTRACT: BACKGROUND: An endogenous circadian clock controls locomotor activity in common spiny mice (Acomys cahirinus). However, little is known about the effects of constant light (LL) on this activity or about the existence of an additional food entrainable clock. A series of experiments were performed to investigate the effects of LL and DD on tau and activity levels. METHODS: Spiny mice were housed individually and their running wheel activity monitored. One group of mice was exposed to LD, DD and several intensities of LL. Another group was exposed to a restricted feeding (RF) paradigm in light: dark (LD) during one hour before the L to D transition. Significance of rhythmicity was assessed using Lomb-Scargle periodograms. RESULTS: In LD all animals exhibited nocturnal activity rhythms that persisted in DD. When animals were exposed to RF (during L), all of these animals (n = 11) demonstrated significant food anticipatory activity as well as an increase in diurnal activity. This increase in diurnal activity persisted in 4/11 animals during subsequent ad libitum conditions. Under LL conditions, the locomotor rhythms of 2/11 animals appeared to entrain to RF. When animals were exposed to sequentially increasing LL intensities, rhythmicity persisted and, while activity decreased significantly, the free-running period was relatively unaffected. In addition, the period in LL was significantly longer than the period in DD. Exposure to LL also induced long-term changes (after-effects) on period and activity when animals were again exposed to DD. CONCLUSIONS: Overall these studies demonstrate clear and robust circadian rhythms of wheel-running in A. cahirinus. In addition, LL clearly inhibited activity in this species and induced after-effects. The results also confirm the presence of a food entrainable oscillator in this species.  相似文献   

15.
Background: This study was conducted to evaluate fibroblast co-culture and Activin A on in vitro maturation and fertilization of mouse preantral follicles. Methods: The ovaries from 12-14-day-old mice were dissected, and 120-150 μm preantral follicles were cultured individually in α-MEM as based medium for 12 days. A total number of 456 follicles were cultured in four conditions: (i) base medium as control group (n = 113), (ii) base medium supplemented with 30 ng/ml Activin A (n = 115), (iii) base medium co-cultured with mouse embryonic fibroblast (n = 113), and (iv) base medium supplemented with 30 ng/ml Activin A and co-cultured with fibroblast (n = 115). Rate of growth, survivability, antrum formation, ovulation, embryonic development and steroid production were evaluated. Analysis of Variance and Duncan test were applied for analyzing. Results: Both co-culture and co-culture + Activin A groups showed significant difference (P<0.05) in growth (on days 4, 6, and 8 of culture period) and survival rates. However, there was no significant difference in antrum formation, ovulation rate, and embryonic development of ovulated oocytes. There were significant differences (P<0.05) in the estradiol production on days 8, 10, and 12 between co-culture + Activin A and the control group. Progesterone production also was significant (P<0.05) in co-culture + Activin A group on days 6, 8, 10, and 12 compared to control group. Conclusion: Fibroblast co-culture and Activin A promoted growth and survivability of preantral follicles. However, simultaneous use of them was more efficient. Key Words: Fibroblast, Activin A, Follicle  相似文献   

16.
The impact of diluted levels of polluted seawater from the Egyptian Mediterranean coast on reproductive, toxicological and hematological characteristics of Siganus rivulatus were determined. Mature fish were exposed to diluted levels of 7.5, 10 and 15 ml L(-1) polluted seawater. Hematological changes after 4, 15 and 30 days of exposure were measured. Erythrocytes decreased (p<0.05) as well as Packed Cell Volume (PCV) and Hemoglobin (Hb), indicating anemia developed to hypochromic macrocytic anemia at end of experiment. Leukocytes, increased (p<0.05), indicating susceptibility of fish to infection and stress. Granulocytic leukocytes, neutrophil and eosinophil increased. While lymphocytes decreased. Blood parameters of exposed fish revealed compensatory responses. The increase in developing hemocytoplast and myelocytes emphasize the compensatory and defensive reaction of fish to polluted water. Exposure to polluted water levels has a detrimental effect on gonads development, altered endocrine haemostasis, testosterone and progesterone levels decreased in females (p<0.05). While in male, progesterone level increased (p<0.01). Necrosis of spermatogenic cells and atresia of developing oocytes are pronounced at levels of 10 and 15 ml L(-1)polluted seawater. Also, has necrotic effect on fish organs. Vacuolation and necrosis occurs in liver and kidney. Melanomacrophage aggregates can be seen. Gills showed epithetial lifting and vascular widening. Results showed that, polluted water has serious consequences on Siganus rivulatus blood characteristics as well as organs cellular structure. It rendered fish anemiatic, altered reproductive hormones level, leading to necrosis of males spermatogenic cells and atresia of developing oocytes.  相似文献   

17.
We have previously demonstrated that the non-digestible fraction (NDF) from common cooked beans (P. vulgaris L., cv Negro 8025) inhibits azoxymethane (AOM)-induced colon cancer and influences the expression of genes involved in the induction of apoptosis and cell cycle arrest through the action of butyrate. The objective of this study was to identify cell cycle alterations and morphological changes induced by treatment with AOM and to examine the formation of colonic aberrant crypt foci (ACF) in male Sprague Dawley rats fed with these beans. Rats were fed control diets upon arrival and were randomly placed into four groups after one week of acclimatization: control, NDF (intragastric administration), NDF?+?AOM and AOM. Rats treated with NDF?+?AOM exhibited a significantly lower number of total colonic ACF with a notable increase in the number of cells present in the G1 phase (83.14 %); a decreased proliferation index was observed in the NDF?+?AOM group when compared to AOM group. NDF?+?AOM also displayed a higher number of apoptotic cells compared to AOM group. NDF of cooked common beans inhibited colon carcinogenesis at an early stage by inducing cell cycle arrest of colon cells and morphological changes linked to apoptosis, thus confirming previous results obtained with gene expression studies.  相似文献   

18.

Background

An endogenous circadian clock controls locomotor activity in common spiny mice (Acomys cahirinus). However, little is known about the effects of constant light (LL) on this activity or about the existence of an additional food entrainable clock. A series of experiments were performed to investigate the effects of LL and DD on tau and activity levels.

Methods

Spiny mice were housed individually and their running wheel activity monitored. One group of mice was exposed to LD, DD and several intensities of LL. Another group was exposed to a restricted feeding (RF) paradigm in light: dark (LD) during one hour before the L to D transition. Significance of rhythmicity was assessed using Lomb-Scargle periodograms.

Results

In LD all animals exhibited nocturnal activity rhythms that persisted in DD. When animals were exposed to RF (during L), all of these animals (n?=?11) demonstrated significant food anticipatory activity as well as an increase in diurnal activity. This increase in diurnal activity persisted in 4/11 animals during subsequent ad libitum conditions. Under LL conditions, the locomotor rhythms of 2/11 animals appeared to entrain to RF. When animals were exposed to sequentially increasing LL intensities, rhythmicity persisted and, while activity decreased significantly, the free-running period was relatively unaffected. In addition, the period in LL was significantly longer than the period in DD. Exposure to LL also induced long-term changes (after-effects) on period and activity when animals were again exposed to DD.

Conclusions

Overall these studies demonstrate clear and robust circadian rhythms of wheel-running in A. cahirinus. In addition, LL clearly inhibited activity in this species and induced after-effects. The results also confirm the presence of a food entrainable oscillator in this species.  相似文献   

19.

Background

Recent studies on humans and rodents have suggested that the timing of food intake plays an important role in circadian regulation and metabolic health. Consumption of high-fat foods during the inactive period or at the end of the awake period results in weight gain and metabolic syndrome in rodents. However, the distinct effects of breakfast size and the breakfast/dinner size ratio on metabolic health have not yet been fully examined in mice.

Methods

We examined whether the parameters of metabolic syndrome were differentially affected in mice that consumed a large meal at the beginning of the awake period (breakfast; one meal group) and a relatively smaller meal at end of the awake period (dinner; two meals group). The mice of each group were provided equal food volume per day.

Results

Mice on one meal exhibited an increase in body weight gain, hyperinsulinemia, hyperleptinemia, and a decrease of gene expression associated with ??-oxidation in adipose tissue and liver compared with those on two meals. The circadian expression pattern of the Clock gene in mice on one meal was disturbed compared with those on two meals.

Conclusions

In conclusion, a bigger breakfast with a smaller dinner (two meals per day) but not breakfast only (one meal per day) helps control body weight and fat accumulation in mice on a high-fat meals schedule. The findings of this study suggest that dietary recommendations for weight reduction and/or maintenance should include information on the timing and quantity of dietary intake.  相似文献   

20.
水稻 (Oryza sativa L.)花粉及花药壁发育的超微结构研究   总被引：11，自引：0，他引：11  
 运用透射电子显微镜技术,系统观察了水稻花粉及其花药壁层的发育过程,发现了一些新的现象：(1)小孢子母细胞减数分裂期间,伴随核内染色体变化的同时细胞质发生了“改组”现象,主要表现为核糖体分布密度的规律性变化,这标志着孢子体向配子体的转变。(2) 小孢子外壁的发育始于四分体晚期,最早表现在四分孢子质膜上沉积了少量的壁物质。随后沉积增多,至小孢子早期即形成初生外壁。此后外壁发育迅速,到小孢子晚期外壁已基本发育完成。(3)小孢子中期,小孢子细胞核的双层核膜局部分开,并逐渐扩张成一个“大泡”。核膜扩张在这一时期是一种普遍现象。(4)在花粉发育过程中,绒毡层细胞结构发生明显变化：小孢子母细胞形成之初,绒毡层细胞结构完整,内质网极少;随着减数分裂的进行,绒毡层胞质浓缩,细胞内出现“空腔”,内质网丰富;到了小孢子中期,仍有较多堆叠的内质网,此后逐渐消失。表明内质网在绒毡层的发育中起着重要的物质合成及运输作用。(5)花粉完全成熟时,花药中层细胞的壁以及绒毡层的外切向壁紧贴在一起,形成了一叠合的“壁”结构。  相似文献   

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