Atretic preovulatory follicles could be precursors of ovarian lutein cysts in the pig.

Ovarian cysts contribute to reduced reproductive performance in pigs. Unfortunately, the mechanism of lutein cysts formation remains unknown. Here, we compared the endocrine and molecular milieus of intact, healthy preovulatory follicles (PF), gonadotropin (eCG/hCG)-induced healthy and atretic-like PF, as well as gonadotropin-provoked and spontaneous ovarian cysts in gilts.

The Role of Reduced Oxygen Supply and Transcription Factors cJUN and CREB in Progesterone Production during the Corpus Luteum Rescue in Gilts.

The corpus luteum plays a fundamental role in regulating reproduction via progesterone production. Still, there is little data on factors regulating the maintenance of luteal function during early pregnancy in gilts. Previous studies emphasize the role of hypoxia and HIF-1 in the regulation of steroidogenic and angiogenic genes expression and progesterone production by ovarian cells.

Attainment of Sexual Maturity and Gonadotropin Priming in Gilts Determine Follicular Development, Endocrine Milieu and Response to Ovulatory Triggers.

The routine procedure of estrous cycle synchronization in pigs allows for the use of gonadotropins to stimulate ovarian activity. The applied protocols of eCG and hFSH priming similarly affected development of ovarian follicles in two classes 3−6 mm and >6 mm of diameter, however, the number of small follicles (<3 mm) was 2-fold higher in hFSH- than in eCG-primed prepubertal gilts. The attainment of sexual maturity increased concentration of estradiol, testosterone and androstenedione in the follicular fluid of hFSH/eCG-primed gilts, however, prostaglandin E2 and F2α metabolite increased in mature hFSH- and eCG-primed gilts, respectively.

Endocrine and molecular milieus of ovarian follicles are diversely affected by human chorionic gonadotropin and gonadotropin-releasing hormone in prepubertal and mature gilts.

Different strategies are used to meet optimal reproductive performance or manage reproductive health. Although exogenous human chorionic gonadotropin (hCG) and gonadotropin-releasing hormone (GnRH) agonists (A) are commonly used to trigger ovulation in estrous cycle synchronization, little is known about their effect on the ovarian follicle. Here, we explored whether hCG- and GnRH-A-induced native luteinizing hormone (LH) can affect the endocrine and molecular milieus of ovarian preovulatory follicles in pigs at different stages of sexual development.

Altrenogest affects the development and endocrine milieu of ovarian follicles in prepubertal and mature gilts†.

Altrenogest with gonadotropins is commonly used to synchronize the estrous cycle, but it can also lead to follicular cyst formation, especially in prepubertal gilts. Here, we aimed to investigate how maturity and altrenogest treatment affect the development, endocrine milieu, and molecular control of ovarian follicles. Crossbred prepubertal and mature gilts were challenged or not (control) with altrenogest, and ovaries were collected in the morning on the first day of behavioral estrus.

The presence of CC chemokines and their aberrant role in the porcine corpus luteum.

The process of luteal regression is tightly regulated by the immune system and chemokines-small cytokines responsible mostly for the activation and migration of immune cells. The role of chemokines in porcine corpus luteum (CL) function is still not well understood. The aim of this study was to investigate the expression profile and distribution of CC chemokines in the porcine CL during the natural oestrous cycle and early pregnancy.

Regulation of the porcine corpus luteum during pregnancy.

The new corpora lutea (CLs) in pigs are formed from the preovulatory follicles after the luteinizing hormone (LH) surge. However, total autonomy and independence of CLs from LH up to Day 12 of cycle has recently been questioned. Transformation of estrous cycle CL to CL of pregnancy initiated by embryonic signals requires not only the cessation of prostaglandin F2 (PGF) supply to the luteal tissue but also needs the CL to overcome luteolytic acquisition and/or changing its sensitivity to PGF during Days 12-14 of pregnancy.

The influence of azaperone treatment at weaning on reproductive function in sows: ovarian activity and endocrine profiles during the weaning-to-ovulation interval.

Azaperone can reduce stress caused by weaning and relocation of breeding sows, but its effects on reproductive processes are still poorly understood. The primary aim of this study was to describe and compare the endocrine and ovarian activity in ultrasonographically monitored second parity sows, with or without azaperone treatment at weaning (2 mg/kg BW i.m.

Embryo-maternal dialogue during pregnancy establishment and implantation in the pig.

Porcine conceptuses secrete pregnancy-recognition signals (estrogens, including estradiol-17β) that inhibit luteolysis, thereby prolonging progesterone production by corpora lutea. The supportive mechanism by which the conceptus also inhibits luteolysis is by shifting endometrial prostaglandin (PG) synthesis to luteoprotective PGE2. Progesterone stimulates endometrial production of factors that are essential for conceptus development.

Seasonal infertility in gilts and sows: Aetiology, clinical implications and treatments.

In gilts and sows, the summer-autumn period often is characterized by reduced fertility. Heat stress and long photoperiods during the warm season can cause a reduction in feed intake and an imbalance of the hypothalamic-hypophysial-ovarian axis. The increased variability in the interval between oestrus onset and ovulation results in an increased number of poorly timed inseminations.

Verbal and Non-verbal Fluency in Adults with Developmental Dyslexia: Phonological Processing or Executive Control Problems?

The executive function of fluency describes the ability to generate items according to specific rules. Production of words beginning with a certain letter (phonemic fluency) is impaired in dyslexia, while generation of words belonging to a certain semantic category (semantic fluency) is typically unimpaired. However, in dyslexia, verbal fluency has generally been studied only in terms of overall words produced.

Adults with developmental dyslexia show selective impairments in time-based and self-initiated prospective memory: Self-report and clinical evidence.

Background: Prospective memory (PM; memory for delayed intentions) would seem to be impaired in dyslexia but evidence is currently limited in scope.

Aims: There is a need, therefore, firstly, to explore PM under controlled conditions using a broader range of PM tasks than used previously and, secondly, to determine whether objectively measured and self-reported PM problems can be found in the same individuals with dyslexia.

Methods And Procedures: The responses of 30 adults with dyslexia were compared with those of 30 IQ-matched adults without dyslexia on a self-report and a clinical measure of PM.

Aberrant effects of altrenogest and exposure to exogenous gonadotropins on follicular cysts appearance in gilts.

Research was conducted to determine the effect of altrenogest and exposure to exogenous gonadotropins on ovarian function in prepubertal and mature gilts. Crossbred, presumably sexually mature gilts (n = 51), were fed with altrenogest for 18 consecutive days and the day after the last feeding with altrenogest, gilts were treated with eCG and 72 hours later challenged with hCG. Animals were slaughtered on Days 10 to 13 of their gonadotropins synchronized estrous cycle.

Bioelectrical activity of porcine oviduct and uterus during spontaneous and induced estrus associated with cyclic hormone changes.

It is widely accepted that uterine contraction is initiated by spontaneous generation of electrical activity at a cellular level in the form of action potentials. Such action potential events, when they involve many myometrial cells and occur in immediate succession, are described by their amplitude and duration. In an effort to improve clinical management of uterine contractions, research has focused on determination of the properties of the reproductive tract's electrical activity under hormonal stimulation.

Self-Reports of Increased Prospective and Retrospective Memory Problems in Adults with Developmental Dyslexia.

Short-term and working memory problems in dyslexia are well-documented, but other memory domains have received little empirical scrutiny, despite some evidence to suggest that they might be impaired. Prospective memory is memory for delayed intentions, whilst retrospective memory relates to memory for personally experienced past events. To gain an understanding of subjective everyday memory experience, a self-report measure designed to tap prospective and retrospective memory was administered to 28 adults with dyslexia and 26 IQ-matched adults without dyslexia.

Executive functions in adults with developmental dyslexia.

Background: Executive functioning (EF) deficits are well recognized in developmental dyslexia, yet the majority of studies have concerned children rather than adults, ignored the subjective experience of the individual with dyslexia (with regard to their own EFs), and have not followed current theoretical perspectives on EFs.

Aims And Methods: The current study addressed these shortfalls by administering a self-report measure of EF (BRIEF-A; Roth, Isquith, & Gioia, 2005) and experimental tasks to IQ-matched groups of adults with and without dyslexia. The laboratory-based tasks tested the three factors constituting the framework of EF proposed by Miyake et al.

Time-based prospective memory in adults with developmental dyslexia.

Prospective memory (PM) is memory for delayed intentions. Despite its importance to everyday life, the few studies on PM function in adults with dyslexia which exist have relied on self-report measures. To determine whether self-reported PM deficits can be measured objectively, laboratory-based PM tasks were administered to 24 adults with dyslexia and 25 age- and IQ-matched adults without dyslexia.

Steroid hormones, prostanoids, and angiogenic systems during rescue of the corpus luteum in pigs.

In order to characterize the transition of the corpora lutea (CL) from acquisition of luteolytic sensitivity to rescue of luteal function: i) the expression of 38 factors associated with steroids, prostanoids, and angiogenic systems and ii) concentrations of the main hormones responsible for maintenance of CL function in cyclic and pregnant pigs were examined. Additionally, the effect of prostaglandin (PG) E2 and F2 α on luteal function during the estrous cycle and pregnancy was evaluated in vitro. Significantly up-regulated gene expression was revealed in CL collected on day 14 of the estrous cycle (CYP19A1, ESR2, PTGS2, HIF1A, and EDN1) and on days 12-14 of pregnancy (SCARB1, PGRMC1, STAR, HSD3B1, NR5A1, PTGFR, PTGER4, and VEGFA).

The Importance of the Canonical Wnt Signaling Pathway in the Porcine Endometrial Stromal Stem/Progenitor Cells: Implications for Regeneration.

The regenerative ability of the endometrium is strongly associated with the presence of adult stem/progenitor cells. Purposes of the present study were (1) to establish the presence of stem/progenitor cells in porcine endometrial stroma using a clonogenic assay and (2) to investigate whether the canonical Wnt pathway affects the potential of stem/progenitor cells to undergo self-renewal or differentiation. The utility of endometrial stromal clones as a model for stem/progenitor studies was evaluated based on these cells' increased expression of mesenchymal stem cell (MSC) marker genes, including CD29, CD73, CD90, and CD105, compared with primary cultured cells.

Functional consequences of knocking down porcine prostaglandin synthases in SK-6 swine kidney cell line.

We hypothesized that in vitro knock-down of the previously cloned genes of prostaglandin synthases will result in a reduction of synthesis, and thus secretion of their respective products, i.e., prostaglandin (PG) E2 or PGF2α.

Evidence for the presence of stem/progenitor cells in porcine endometrium.

A population of adult stem cells responsible for cyclic reconstructing and remodeling has been proposed to reside in the highly regenerative mammalian endometrium. Recently, stem/progenitor cells have been identified in the human and mouse endometrium, but less is known about these cells in livestock animals. Using Hoechst 33342 fluorescent dye staining and flow cytometry, we identified an emerging cell side population that may be responsible for the regeneration process of the porcine endometrium.

Expression of factors associated with apoptosis in the porcine corpus luteum throughout the luteal phase of the estrous cycle and early pregnancy: their possible involvement in acquisition of luteolytic sensitivity.

The studies on the acquisition of luteolytic sensitivity have been focused mainly on molecular changes induced in the luteal tissue after treatment with exogenous PGF2α or on physiological changes occurring during the estrous cycle. The comparison of changes leading to the acquisition of luteolytic sensitivity after Day 12 of the estrous cycle and corresponding days of pregnancy has not been investigated in the pig. The present study was undertaken to evaluate (1) apoptosis measured as the proportions of early apoptotic, late apoptotic, and viable cells; (2) expression of factors involved in the extrinsic (TNFA/TNFα, TNFRSF1A/TNFR1, TNFRSF1B/TNFR2, FAS/Fas, and FASLG/FasL) and intrinsic (CASP3/Casp3, TP53/p-53, BAX/Bax, and BCL2/Bcl-2) apoptotic pathways, with two components of the activating protein-1 complex, i.

Effect of oestrus synchronization with PGF2α/eCG/hCG on luteal P4 synthesis in early pregnant gilts.

Administration of hormones to synchronize oestrus is a useful tool in animal breeding. However, exogenous ovarian stimulation may be detrimental to reproductive function. This study was aimed to examine whether an oestrus synchronization with PGF2α/eCG/hCG could affect luteal P4 synthesis in early pregnant gilts.

Precision-cut luteal slices: a promising approach for studying luteal function in pigs.

The study was aimed to validate the precision-cut luteal slices to investigate porcine luteal function. Corpora lutea (CLs) were cut into 180-μm thick slices using Krumdick Tissue Slicer. The viability, tissue structure and steroidogenic acute regulatory protein (STAR) expression in the luteal slices did not differ between the beginning and the end of the 24-h incubation period.