Early diagnosis of septic arthritis is very important. Few studies showed diagnostic accuracy of serum inflammatory markers in septic arthritis. The aim of our study was to compare the serum and synovial fluid markers [procalcitonin, serum IL-6, TNF-α, C-reactive protein, erythrocyte sedimentation rate, synovial fluid white blood cell counts and ...

Whilst micafungin serum concentrations are well studied, little is known about its concentrations within cellular compartments of the peripheral blood. Hence, in this study blood samples were collected from patients receiving micafungin (n=26). These samples were separated by double-discontinuous Ficoll-Hypaque density gradient centrifugation. Intracellular concentrations within the obtained cells, i.e. ...

OBJECTIVE: Neutrophil gelatinase-associated lipocalin (NGAL) plasma concentrations have been associated with cardiovascular diseases. We aimed to assess the association of NGAL with abdominal aortic aneurysm (AAA). METHODS: NGAL concentrations were analyzed by Western blotting in conditioned medium of polymorphonuclear neutrophils (PMNs) from AAA patients (n=22) and controls (n=11), and also ...

The objective was to determine the effects of boar seminal plasma and hen's egg yolk on chemotaxis and phagocytosis of porcine and bovine polymorphonuclear neutrophils (PMNs) in vitro. Chemotactic activity of PMNs was determined following culture for 90 min in a blind well chamber. Phagocytosis was assayed after co-culture of ...

BACKGROUND: Acute chest syndrome (ACS) in sickle cell disease is associated with elevation of secretory phospholipase A(2) (sPLA(2) ). We hypothesize that sPLA(2) cleaves membrane lipids from sickled red blood cells (RBCs) causing PMN-mediated endothelial cell injury (ECI) as the second event in a two-event model. METHODS: Whole blood was ...

To investigate the terminal arteriolar network structure and function in relation to circulating plasma cytokine levels in db/db, ob/ob, and their genetic background control, C57/bl6, mice. Arteriolar network size and erythrocyte distribution were observed in the resting cremaster muscle (n = 45, pentobarbital 50 mg/kg i.p.). Structural remodeling and inflammatory ...

Post-traumatic hypopituitarism is well described amongst adult traumatic brain injury (TBI) survivors. We aimed to determine the prevalence and clinical significance of pituitary dysfunction after head injury in childhood. Retrospective exploratory study. 33 survivors of accidental head injury (27 boys). Mean (range) age at study was 13·4 years (5·4-21·7 years) ...

Poly(ethylcyanoacrylate) (PECA) nanoparticles containing the chemical sterilitant D-Lys(6)-GnRH were prepared by an in situ interfacial polymerization technique. Their potential as a peroral delivery system for biocontrol of the brushtail possum, a major pest species in New Zealand, was evaluated. Peptide release from resulting particles was studied in vitro in artificial ...

GnRH (gonadotrophin releasing hormone) is a key hormone of reproductive function in mammals; agonist forms have been largely developed, and data concerning their use in small animal reproduction are now abundant. GnRH agonists act by a two-step mechanism. First, their agonist properties on the pituitary will cause marked LH (luteinizing ...

The magnitude of the LH surge after GnRH agonist "trigger" was correlated with oocyte yield and maturity and was suboptimal in approximately half of the cycles. A modest reduction in oocyte yield and maturity was observed when the serum level of LH 12 hours after GnRH agonist trigger was less ...

Gonadotropin-releasing hormone (GnRH) secretion has two modes of release in mammalian species; the surge mode and the pulse mode. The surge mode, which is required for the induction of the preovulatory gonadotropin discharge in most species, is induced by the positive feedback of estrogen secreted by the mature ovarian follicle. ...

Early studies on gonadotrophin-releasing hormone (GnRH) antagonists pointed out histamine-mediated anaphylactic reactions as a potential adverse effect of these drug candidates. In this study we have compared the histamine-releasing potential of four approved and marketed antagonists, degarelix, cetrorelix, abarelix and ganirelix in an ex vivo model of human skin samples. ...

Puberty in primates is first delayed by a neurobiological switch that arrests pulsatile GnRH release during infancy and then triggered, after a protracted period of juvenile development, by resurgence in intermittent release of this hypothalamic peptide. The purpose of this chapter is to review recent studies conducted in our laboratories ...

Increasing evidence supports GnRH agonists to be an effective treatment to preserve ovarian function during chemotherapy, but the initial flare-up of FSH during the first week after GnRH agonist application still limits its use. The combination of GnRH agonists with GnRH antagonists might solve this problem to some extent as ...

Birds from the temperate and cold zones show annual sexual activity accompanied by gonadal changes and fluctuation in their brain gonadotropin-releasing hormone (GnRH) levels. However, most of the studies were done on captive birds where the constant environment can profoundly modify periodical changes. Therefore our aim was to reveal annual ...

Because the effectiveness of the "microdose flare" stimulation protocol often is attributed to the dramatic endogenous gonadotropin release induced by the GnRH agonist, the aim of this study was to determine whether use of microdose GnRH agonist alone could induce multiple ovarian follicle development in normal responders. Based on these ...

Lactation is an important physiological model of the integration of energy balance and reproduction, as it involves activation of potent appetitive neuropeptide systems coupled to a profound inhibition of pulsatile GnRH/LH secretion. There are multiple systems that contribute to the chronic hyperphagia of lactation: 1) suppression of the metabolic hormones, ...

Sea lampreys are anadromous and semelparous, i.e., they spawn only once in their lifetime, after which they die. Sexual maturation is thus a synchronized process coordinated with the life stages of the lamprey. Recently, a novel gonadotropin-releasing hormone, lamprey GnRH-II (lGnRH-II), was identified in lampreys and suggested to have a ...

Based on the supposition that lamprey GnRH-III (lGnRH-III) elicits FSH releasing activity in swine, synthetic lGnRH-III (peforelin, Maprelin® XP10) was used in puberal estrus synchronized gilts. The secretion of reproductive hormones FSH, LH, estradiol and progesterone was analyzed, and follicle growth and ovulation recorded. Altogether, 24 German Landrace gilts were ...

Gonadotropin-releasing hormone (GnRH) is the key hormone regulating reproduction. Its feedback regulation is exercised by estradiol. The early postnatal period is critical for sexual differentiation. Despite the fact that malnutrition-related reproductive suppression in rats is a well-documented phenomenon, we had no knowledge, until now, on how maternal malnutrition affects GnRH ...

We used a free-ranging, seasonally breeding adult male songbird, the rufous-winged sparrow, Aimophila carpalis, to investigate the effects of acute stress-induced by capture followed by restraint, on the hypothalamo-pituitary-testicular axis. Intra- and interindividual comparisons revealed that males decreased their plasma testosterone (T) by 37-52% in response to acute stress. The ...

To evaluate whether the incidence of luteinizing hormone (LH) rise is reduced by using a flexible compared with a fixed day-6 protocol of GnRH antagonist administration. Randomized controlled trial. Tertiary university hospital. Patients undergoing in vitro fertilization (n = 146). Ovarian stimulation was performed using recombinant FSH and GnRH antagonists. ...

Adult-onset idiopathic hypogonadotropic hypogonadism (AHH) is a rare disorder characterized by an isolated failure of gonadotropin secretion occurring after an otherwise normal sexual maturation in men. This study aims to examine the etiology and long-term natural history of this disorder. Long-term follow up, including detailed clinical, biochemical, and genetic examinations, ...

Allopregnanolone, a neuroactive steroid mainly secreted by adrenals and gonads, is a hormone that seems to play a role in precocious puberty, as demonstrated by its high baseline levels found in girls with central precocious puberty (CPP). Allopregnanolone concentrations significantly increase after GnRH and ACTH stimulation test suggesting both its ...

To determine if intermittent, low-dose, short-acting gonadotropin-releasing hormone agonist (GnRH-agonist) administration sufficiently up-regulates pituitary-gonadal function in gonadotropin deficiency to be of diagnostic or therapeutic value. Case-control study. General clinical research center. Normal adult volunteers and gonadotropin-deficiency patients. Low-dose leuprolide acetate administered subcutaneously at 4- to 5-day intervals up to 1 ...

We examined whether progesterone (P4)-induced suppression of LH release in cattle can be overcome by an increased dose of exogenous gonadotropin-releasing hormone (GnRH) or pretreatment with estradiol (E2). In Experiment 1, postpubertal Angus-cross heifers (N = 32) had their 2 largest ovarian follicles ablated 5 d after ovulation. Concurrently, these ...

These experiments investigated the involvement of gonadotrope progesterone receptor (PR) in the effects of the putative gonadotropin surge-attenuating factor (GnSAF) on gonadotropin (LH and FSH) secretion. Human follicular fluids (hFF) used in this study were aspirated from follicles in gonadotropin-treated women for in vitro fertilization. Samples were subjected to two-fold ...

The identification of the neural mechanisms controlling ovulation in mammals has long been a 'holy grail' over recent decades, although the recent discovery of the kisspeptin systems has totally changed our views on this subject. Kisspeptin cells are the major link between gonadal steroids and gonadotrophin-releasing hormone (GnRH) neurones. In ...

Gonadotropin-releasing hormone (GnRH) is the first key hormone of reproduction. GnRH analogs are extensively used in in vitro fertilization and treatment of sex hormone-dependent cancers due to their ability to bring about 'chemical castration'. Recently it has been showed that it also plays an important role in the modulation of ...

Relatively little is known about the physiological response and mortality consequences of the return of anadromous fish to freshwater (FW). We explored the consequences of the return to FW by collecting maturing sockeye salmon from the marine waters off the mouth of the Fraser River and holding approximately 50 sockeye ...

BACKGROUND: GnRH antagonists have been introduced to induce persistent LH suppression. Many studies show a gradual increase of LH levels after several days of GnRH antagonist administration, the so-called escape or rebound effect. We hypothesize that, under chronic GnRH antagonist administration, a higher pituitary response to GnRH could be an ...

Idiopathic hypogonadotropic hypogonadism (IHH) with normal smell (normosmic IHH) or anosmia (Kallmann syndrome) is associated with defects in the production or action of GnRH. Accordingly, most IHH patients respond to physiological pulsatile GnRH replacement by normalizing serum LH, FSH, and testosterone (T) levels and achieving gametogenesis; some patients, however, show ...

An immune/inflammatory challenge can affect reproduction at the level of the hypothalamus, pituitary gland, or gonads. Nonetheless, the major impact is thought to occur within the brain or the pituitary gland. The present study was designed to examine the effect of intravenous (i.v.) lipopolysaccharide (LPS) injection on the expression of ...

Gonadotrophin-releasing hormone (GnRH) agonists and antagonists have been widely used to prevent premature LH surge during ovarian stimulation. However, studies have shown a significantly lower serum oestradiol concentration on the day of human chorionic gonadotrophin administration for cycles using GnRH antagonist. This study compared aromatase gene expression in granulosa lutein ...

Ovarian steroids normally exert homeostatic negative feedback on GnRH release. During sustained exposure to elevated estradiol in the late follicular phase of the reproductive cycle, however, the feedback action of estradiol switches to positive, inducing a surge of GnRH release from the brain, which signals the pituitary LH surge that ...

In ewes, immunization against GnRH blocks LH pulses but mean serum FSH concentrations are only partly reduced; the fate of the FSH peaks that precede ovarian follicular waves has not been studied. In this study, we used immunization against GnRH to examine the need for pulsed GnRH secretion in the ...

The aims of the present study were to clarify the effect of kisspeptin-10 (Kp10) on the secretion of luteinizing hormone (LH), follicle stimulating hormone (FSH), growth hormone (GH) and prolactin (PRL) in goats, and compare the characteristics of any response with those of the response to gonadotropin-releasing hormone (GnRH). The ...

Studies in humans and animals indicate that estrogen negative feedback occurs at the level of the hypothalamus, but it is unclear whether estrogen also exerts an inhibitory effect directly at the pituitary. The aim of the study was to determine whether estrogen has a direct negative feedback effect at the ...

Reproductive function depends on the stimulatory action of gonadotropin-releasing hormone (GnRH), secreted by the brain. Original work in birds identified and isolated a peptide that inhibits gonadotropin release, named gonadotropin inhibitory hormone (GnIH). There is no evidence for a similar factor operant in mammals. This mammalian orthologue of GnIH has ...

The neuropeptide gonadotropin-releasing hormone (GnRH) plays a key regulatory role in mammalian reproduction. It is synthesized by hypothalamic neurons and released from nerve endings into the portal circulation. After binding to membrane GnRH type 1 receptors on gonadotropic cells of the anterior pituitary, it stimulates the synthesis and release of ...

There is continuing need to simplify bovine superovulation protocols without compromising embryo production. The control of follicular wave emergence and ovulation has facilitated donor management, but the most commonly used treatment, oestradiol, cannot be used in many parts of the world and mechanical removal of the dominant follicle is difficult ...

Reproductive activities of salmonids are synchronized by changes in photoperiod, which control the endocrine system via the brain-pituitary-gonadal axis. Gonadotropin-releasing hormone (GnRH) in the brain regulates synthesis and release of the pituitary gonadotropins (GTHs; FSH and LH). FSH and LH in turn stimulate the production of sex steroids for oocyte ...

To test the hypothesis that the hypothalmic gonadotropin-releasing hormone (GnRH) and testosterone (T) co-treatment stimulates both the hypothalmo-pituitary-gonadal (HPG) and hypothalmo-pituitary-interrenal axes, the reproductive and osmoregulatory responses of pre-adult pink salmon Oncorhynchus gorbuscha were compared after GnRH and T administration either alone or in combination. Relative to controls, neither GnRH ...

Using morphological criteria we describe the effect of maternal deprivation on the gonadotrophin-releasing hormone (GnRH) and GnRH-associated peptide (GAP) of the GnRH prohormone (proGnRH) in the preoptic area (POA)-hypothalamus during the weaning period. The immunohistochemical GnRH- and GAP-neuroanatomy was investigated in female 12-week-old weanling and maternally deprived lambs and 15-week-old ...

Hormone-secreting glands communicate via intermittent (pulsatile or rhythmic) signal exchange. Signals act upon target glands via implicit (not directly observable) stimulatory and inhibitory dose-response functions. Time delays operate, since secreted hormones do not arrive at or act on responsive cells instantaneously. Neuroendocrine systems are unique examples, therefore, of intermittent time-delayed ...

BACKGROUND: It is well known that many anurans do not reproduce easily in captivity. Some methods are based on administration of mammalian hormones such as human chorionic gonadotropin, which are not effective in many frogs. There is a need for simple, cost-effective alternative techniques to induce spawning. METHODS: Our new ...

BACKGROUND: We demonstrated that E2 conjugated to BSA (E2BSA) induces a rapid membrane-initiated inhibition of LH secretion followed hours later by a slight increase in LH secretion. Whether these actions of E2BSA are restricted to the pituitary gland and whether the membrane-initiated pathway of E2BSA contributes to the up-regulation of ...

Growing evidence suggests the tachykinin neurokinin B (NKB) may modulate gonadotrophin secretion and play a role in sex-steroid feedback within the reproductive axis. NKB signalling has recently been identified as being necessary for normal human reproductive function, although the precise mechanisms underpinning this role remain to be established. We have ...

The possible relationship between endogenous LH concentrations and clinical outcome was evaluated in 750 patients treated with a standardized gonadotrophin-releasing hormone (GnRH) antagonist and recombinant FSH (rFSH)-only protocol. Serum LH concentrations were measured during stimulation by a central laboratory and patients were stratified into quantiles of <P25, P25-P75, and >P75. ...

Hormonal therapy is the main recommended treatment for locally advanced and metastatic prostate cancer. Luteinizing hormone-releasing hormone (LHRH) agonists, such as buserelin, goserelin, leuprorelin and triptorelin, stimulate the pituitary's gonadotrophin-releasing hormone (GnRH) receptor, ultimately leading to its de-sensitization and subsequent reduction of LH and testosterone levels. However, this reduction is ...