Search Results
Results 301 - 350 of 1906
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Pangas Stephanie A - - 2006
SMAD4 is a central component of the TGFbeta superfamily signaling pathway. Within the ovary, TGFbeta-related proteins play crucial roles in controlling granulosa cell growth, differentiation, and steroidogenesis. To study the in vivo roles of SMAD4 during follicle development, we generated an ovarian conditional knockout of Smad4 using the cre/loxP recombination ...
Nynca Anna - - 2006
Genistein affects reproductive processes in animals. However, the mechanism of its action is not fully elucidated and differs among species. The objectives of the current study were: 1/ to establish an in vitro model of granulosa cell culture for studying the intracellular mechanism of phytoestrogen action in porcine ovary; 2/ ...
Peluso J J - - 2006
The effect of granulosa cell contact on the ability of zona-free oocytes to undergo germinal vesicle breakdown (GVBD) was assessed using a granulosa cell co-culture system. Oocytes contacted granulosa cells in a site-specific manner such that their GV was away from the granulosa cells. Also contact with granulosa cells reduced ...
Chan Carina C W - - 2006
The incidence of the 4,977-bp deletion in mitochondrial DNA (DeltamtDNA4977) in 73 pairs of granulosa and cumulus oophorus cells was studied with polymerase chain reaction (PCR), and was significantly higher in granulosa cells (GC) (67/73, 91%) than in cumulus oophorus cells (17/73, 23.3%), independent of the donors' age. In the ...
Vanholder T - - 2006
In this study, the effects of beta-OH butyrate (BHB) levels, associated with a negative energy balance, on bovine granulosa and theca cell function were investigated in vitro. Granulosa and theca cells of healthy large follicles (>8 mm), obtained from slaughterhouse ovaries, were cultured in serum free medium containing 0, 0.5, ...
Hutt K J - - 2006
Paracrine signalling between the oocyte and its surrounding somatic cells is fundamental to the processes of oogenesis and folliculogenesis in mammals. The study of animal models has revealed that the interaction of granulosa cell-derived kit ligand (KL) with oocyte and theca cell-derived c-Kit is important for multiple aspects of oocyte ...
Sutton-McDowall Melanie L - - 2006
Glucose concentration during cumulus-oocyte complex (COC) maturation influences several functions, including progression of oocyte meiosis, oocyte developmental competence, and cumulus mucification. Glucosamine (GlcN) is an alternative hexose substrate, specifically metabolized through the hexosamine biosynthesis pathway, which provides the intermediates for extracellular matrix formation during cumulus cell mucification. The aim of ...
Johnson P A - - 2006
Activin A has been shown to be abundant in the theca layer of the large pre-ovulatory follicles of the hen whereas inhibin A is produced in the granulosa layer. The purpose of this study was to investigate the effects of activin A and inhibin A on granulosa cell expression of ...
Simon Alexander M - - 2006
In the ovarian follicle, granulosa cells adjacent to the oocyte extend processes through the zona pellucida matrix, and these projections establish gap junctions both with the oocyte and with neighboring transzonal projections. The identity of connexins contributing to gap junctions between transzonal projections has not been extensively studied. Here, we ...
Areekijseree Mayuva - - 2006
The morphology and structure of porcine oviductal epithelial cells (POEC), cumulus-oocyte complexes (COCs) and granulosa cells (GC) were investigated in vivo and in vitro conditions using scanning electron microscopy (SEM) and inverted microscopy. The POEC contained columnar ciliated cells and spherical shaped non-ciliated cells. Both non- and ciliated cells appeared ...
Tománek Milan - - 2006
The aim of the study was to determine the expression of proliferating cell nuclear antigen protein (PCNA) in the pig ovary. The localization of PCNA was demonstrated in paraffin sections of pig ovarian tissue using primary mouse monoclonal anti-PCNA antibody. In primordial follicles, no remarkable staining for PCNA either in ...
Nishida Takashi - - 2006
BACKGROUND: The existing dogma that the former term ovarian "germinal epithelium" resulted from a mistaken belief that it could give rise to new germ cells is now strongly challenged. DISCUSSION: Two years ago, a research group of the University of Tennessee led by Antonin Bukovsky successfully demonstrated the oogenic process ...
Shao Ruijin - - 2006
The small ubiquitin-related modifier-1 (SUMO-1) with broad cellular expression has been implicated in a range of cellular processes, such as cell proliferation, differentiation, and apoptosis. As shown recently, SUMO-1 is expressed and regulated by gonadotropins, in particular an ovulatory hCG stimulus in mouse granulosa cells in vivo. To test the ...
Quinn M C J - - 2006
Human follicular fluid can provide a source of human granulosa cells for scientific study. However, removing potentially contaminating cells, such as white and red blood cells, is important for molecular and in vitro studies. We have developed a purification technique for human granulosa cells based on the selection of cellular ...
Griffin Jeanine - - 2006
BACKGROUND: Laboratory animals are commonly used for evaluating the physiological properties of the mammalian ovarian follicle and the enclosed oocyte. The use of different species to determine the morphological relationship between the follicle and oocyte has led to a recognizable pattern of follicular stages, but differences in follicle size, oocyte ...
Brasset E - - 2006
BACKGROUND: Retroviruses have evolved various mechanisms to optimize their transfer to new target cells via late endosomes. Here, we analyzed the transfer of ZAM, a retroelement from Drosophila melanogaster, from ovarian follicle cells to the oocyte at stage 9-10 of oogenesis, when an active yolk transfer is occurring between these ...
Kotwica Jan - - 2006
Ovarian, endometrial and myometrial cells and strips of longitudinal myometrium from cows on defined days of estrous cycle were treated for 24-72 h with different doses (1-100 ng/ml) of PCBs mixture (Aroclor 1248) or with one of PCB congeners (126, 77, 153). The administered doses of PCBs neither affected the ...
Thomas Fiona H - - 2006
Ovarian folliculogenesis is regulated by both endocrine and intraovarian mechanisms that coordinate the processes of oocyte growth and somatic cell proliferation and differentiation. Within the follicle, paracrine interactions between the oocyte and surrounding granulosa cells are critical for normal cell development and function. This review focuses on the role of ...
Wojtowicz Anna - - 2005
OBJECTIVE: In our previous papers, we demonstrated that TCDD and PCBs (both coplanar PCB 126 and non-coplanar PCB 153) caused the decreased estradiol secretion in cultured pig ovarian follicles. However, the mechanism of action is not clearly understood. Moreover, to our knowledge, the expression of AhR in pig follicular cells ...
Brunet Stephane - - 2005
During meiotic maturation of mammalian oocytes, two successive divisions occur without an intermediate phase of DNA replication, so that haploid gametes are produced. Moreover, these two divisions are asymmetric, to ensure that most of the maternal stores are retained within the oocyte. This leads to the formation of daughter cells ...
Yoshida Hiroyuki - - 2005
Border cell migration is a process that occurs during Drosophila ovarian development in which cells derived from a simple epithelium migrate and invade neighboring tissue. This process resembles the behavior of cancerous cells that derive from the simple epithelium of the human ovary. One important regulator of border cell migration ...
Kamei Hiroyasu - - 2006
To clarify the physiological functions of follicle-stimulating hormone (FSH) during oogenesis in Japanese eel, Anguilla japonica, the steroidogenic activities of recombinant Japanese eel FSH (rjeFSH) were assessed in the eel ovary. Female eel were injected with salmon pituitary homogenate to enhance the ovarian development, and the ovaries at different developmental ...
Harfst Eva - - 2005
The peripheral B-cell pool is in dynamic equilibrium and is controlled by a variety of factors. The rate of generation of B cells can influence both the composition and size of the peripheral B-cell compartment. Mice deficient for lambda5 gene expression have a block in early B-cell development leading to ...
Liu Hongshan - - 2005
PURPOSE: This study investigates the presence of M cells in the rabbit conjunctiva. Resolving whether the conjunctiva contains M cells is important, because at other mucosal sites, these antigen sampling cells are known to initiate the mucosal immune response and to act as a site of entry for opportunistic pathogens. ...
Alibardi L - - 2005
The present ultrastructural study describes the formation of feather ramification in developing juvenile feathers of the zebrafinch, a small passeraceous bird. The study stresses the importance of the detailed knowledge on the cell structure of barb ridges for the understanding of feather development and evolution. Feather formation depends on the ...
Gittens Joanne E I - - 2005
The gap junction proteins connexin37 and connexin43 are required for ovarian folliculogenesis in the mouse. To define their respective roles in oogenesis, chimeric ovaries containing either null mutant oocytes and wild-type granulosa cells or the reverse combination were grafted to the renal capsules of immunodeficient female mice. After three weeks, ...
Srivastava Bhaskar - - 2005
Selection of recently formed B cells into the follicular or marginal zone (MZ) compartments is proposed to occur by way of proliferative intermediates expressing high levels of CD21/35 and CD23. However, we show that CD21/35(high) CD23(+) splenocytes are not enriched for proliferative cells, and do not contribute substantially to the ...
Lee Kangseok - - 2005
Blepharophimosis-ptosis-epicanthus inversus syndrome type I is an autosomal disorder caused by mutations in FOXL2 gene and associated with premature ovarian failure in women by a dominant inheritance. FOXL2 is a recently identified protein that belongs to forkhead family transcription factor, of which signaling pathways are still unknown. Here, we show ...
Robinson R S - - 2006
The timing of the post-ovulatory progesterone rise is critical to the embryonic development and survival. The aim of this study was to determine the underlying causes of delayed post-ovulatory progesterone rises. Two groups of non-lactating dairy cows with early (n = 11) or late (n = 9) post-ovulatory progesterone rises ...
Ali Al Ahmad M Z - - 2005
The aim of this study was to determine whether oocytes taken from ovarian follicles in 123 naturally infected goats were carrying the proviral CAEV genome. Examination of DNA isolated from 190 batches of oocytes with intact cumulus cells and 190 batches of oocytes whose cumulus cells had been removed, taken ...
Mazurkiewicz Marta - - 2005
To gain insight into the evolution of differentiation pathways that are involved in the follicular cells' morphogenesis in dipteran ovaries we have undertaken the comparative morphological analysis of the follicular cell behavior in crane flies, representatives of more ancestral nematocerous flies. This analysis revealed that initially the organization of the ...
Nourani Mohammad Reza - - 2005
The localization of adipocyte-type fatty acid binding protein (A-FABP) in the mature mouse ovary was examined by immuno-light and electron microscopy. Solitary round cells showing the distinct immunoreactivity for A-FABP were detected in 1-6 antral follicles. In sets of two consecutive sections in a mirror alignment on slide glasses which ...
Drummond Ann E - - 2005
Ovarian development begins back in the embryo with the formation of primordial germ cells and their subsequent migration and colonisation of the genital ridges. Once the ovary has been defined structurally, the primordial germ cells transform into oocytes and become housed in structures called follicles (in this case, primordial follicles), ...
Tworzydlo Waclaw - - 2005
In all higher dipterans (Brachycera), including the fruitfly, Drosophila melanogaster, each egg chamber (ovarian follicle) consists of a group (clone) of germ cells (one oocyte and 15 accompanying nurse cells) that is surrounded by a layer of somatic mesodermal follicular cells (FCs). As oogenesis progresses the initially uniform FCs diversify ...
Nampoothiri Laxmipriya P - - 2006
Lead (Pb) and cadmium (Cd) are known reproductive toxicants, which accumulate in granulosa cells of the ovary. Female Charles foster rats were treated with sodium acetate (control), lead acetate and cadmium acetate either alone or in combination at a dose 0.05 mg/kg body weight intra-peritoneally for 15 days daily. Animals ...
Forges T - - 2005
Sex hormone-binding globulin (SHBG), a hepatic carrier protein for sex steroids is expressed in different steroid-sensitive tissues, including Sertoli cells of the testis. It has been suggested that this protein may be one of the local regulators of spermatogenesis. The expression of SHBG in the ovary is currently unknown. We ...
Kaleli Semih - - 2005
We performed a prospective study to detect the cell cycle changes in luteinized granulosa cells in patients undergoing controlled ovarian stimulation with GnRH analog and gonadotropin therapy. Aneuploid DNA content was observed in 37 of 70 women (52.9%), and multiple logistic regression analysis revealed that only the dose of gonadotropins ...
Jeschke Udo - - 2005
BACKGROUND: Phytoestrogens are a diverse group of non-steroidal compounds that occur naturally in many plants. Because they possess a ring system similar to estrogens they are able to bind to estrogen receptors in humans. In the present study we tested the effects of the phytoestrogens genistein and daidzein on the ...
Tong Dan - - 2006
Genetic ablation of connexin37 (Cx37) or connexin43 (Cx43), the two gap junction proteins expressed by mouse ovarian granulosa cells, has been shown to result in impaired follicle development. We used patch-clamp techniques to evaluate quantitatively the contribution of these connexins to gap junctional intercellular communication (GJIC) among granulosa cells. The ...
D'haeseleer M - - 2006
Apoptosis was localized in all ovarian cell types of 23 cows in various stages of the oestrous cycle, using the detection of active caspase-3, in situ end labelling (TUNEL) and DNA fluorescent staining (DAPI). Very few apoptotic cells were found in primordial, primary, secondary and vital tertiary follicles. In contrast, ...
Agarwal Rachana - - 2005
Claudin proteins form a large family of integral membrane proteins crucial for tight junction formation and function. Our previous studies have revealed that claudin-3 and claudin-4 proteins are highly overexpressed in ovarian cancer. To clarify the roles of claudins in ovarian tumorigenesis, we have generated human ovarian surface epithelial (HOSE) ...
Liu Jing-Xia - - 2005
In vertebrates, folliculogeneis establishes an intricate system for somatic cell-oocyte interaction, and ultimately leads to the acquisition of their respective competences. Although the formation process and corresponding interactions are strikingly similar in diverse organisms, knowledge of genes and signaling pathways involved in follicle formation is very incomplete and the underlying ...
Przybylska-Gornowicz Barbara - - 2005
OBJECTIVE: The study was performed to analyze structural changes of the turkey pineal during the post-hatching development. MATERIAL AND METHODS: The pineals were collected from male turkeys at the age of 1 day, 2, 8, 22, 56 weeks and subjected to histological investigations including morphometrical analyses. The pinealocytes were identified ...
Cheng Yuan - - 2005
Gap junctions contain channels that connect neighboring cells by allowing the movement of molecules smaller than 1,200 Da. They are formed by connexins and may play a crucial role in the regulation of apoptotic cell death. To determine the role of connexin 43 (Cx43), which is dominantly expressed in granulosa ...
Ruiz-Cortés Z Tatiana - - 2005
Cells of the ovarian follicle undergo extensive proliferation and differentiation from the time that the follicle escapes from the primordial state to its acquisition of ovulatory capacity. We examined the dynamic modification of the phosphorylation state of the histone H3 N-terminal tail in granulosa cells during follicular development. In rodent ...
Lawrence Janelle L - - 2005
The objective was to evaluate development of cloned embryos constructed with serum-starved versus fed ovarian granulosa cells. Fusion of somatic cells with cytoplasts (50.7 and 50.7%; SEM=5.5), development of cloned embryos to 8-16-cell (59.4 and 62.6%; SEM=6.4), and compact morula/blastocyst-stages (24.9 and 26.5%; SEM=8.5) was similar for serum-starved and fed ...
Magoffin Denis A - - 2005
Theca cells are the endocrine cells associated with ovarian follicles that play an essential role in fertility by producing the androgen substrate required for ovarian estrogen biosynthesis. Theca cells differentiate from the interfollicular stroma in response to proteins secreted from growing follicles. The most common endocrine cause of infertility is ...
Kawagishi Rikako - - 2005
OBJECTIVE: The development and maturation of the ovarian follicles are characterized by structural changes that require components involved in cell-cell adhesion systems. Recently a novel group of cell adhesion molecules named nectins has been identified. The present study examined expression and cell-specific localization of nectins during mouse follicular development. STUDY ...
Duffy Diane M - - 2005
CONTEXT: Prostaglandins (PGs) produced within ovarian follicles in response to the ovulatory gonadotropin surge are essential for follicle rupture and oocyte release. Arachidonic acid, the common precursor for PG synthesis, is cleaved from membrane phospholipids via the activity of phospholipase A2 (PLA2). OBJECTIVE: The purpose of this study was to ...
Dziewulska-Szwajkowska Daria - - 2005
The distribution of F-actin, beta-tubulin, aldolase, and fructose-1,6-bisphosphatase (FBPase) in ovarioles of four heteropteran species (Ilyocoris cimicoides, Coreus marginatus, Lygus pratensis, and Notostira elongata) was investigated biochemically and immunocytochemically. Aldolase was found to be uniformly distributed in the cytoplasm of trophocytes and follicular cells, with the highest concentration in prefollicular ...
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