Autocrine/paracrine regulation of breast cancer cell proliferation by growth hormone releasing hormone via Ras, Raf, and mitogen-activated protein kinase.

Although GHRH has previously been shown to regulate proliferation of breast cancer cells and prevent apoptosis, the intracellular pathways mediating this effect have not been clarified. Exogenous GHRH stimulated a dose-dependent proliferative response within 24 h in MDA-231, as well as in T47D cells and in MCF-7 cells transfected with the GHRH receptor. The proliferation of MDA-MB-231 (MDA-231) cells was associated with an increase in tritiated thymidine uptake.

Differential regulation of cell growth and gene expression by FGF-2 and FGF-4 in pituitary lactotroph GH4 cells.

Fibroblast growth factors, FGF-2 and FGF-4, are reported to play divergent roles in pituitary differentiation and tumor formation, stimulating cell differentiation or proliferation, respectively. However, mitogenic responses to FGFs have not been extensively characterized and little is known about the molecular mechanisms by which specific FGF isoforms may mediate distinct biological responses. Here we show that FGF-4 but not FGF-2 stimulated DNA synthesis and cell proliferation in GH4 cells.

The impact of anxiety on sexual arousal in women.

This study examined the impact of state anxiety, trait anxiety, and anxiety sensitivity on physiological and self-report measures of sexual arousal and sexual function in a non-clinical sample of women. Physiological sexual responses to an erotic stimulus were assessed using vaginal photoplethysmography, and subjective reactions were measured using questionnaires. Results suggested a curvilinear relationship between state anxiety and physiological sexual arousal (vaginal pulse amplitude; VPA).

Does episodic hypoxia affect upper airway dilator muscle function? Implications for the pathophysiology of obstructive sleep apnoea.

Obstructive sleep apnoea (OSA) is characterised by repetitive collapse of the upper airway during sleep owing to a sleep-related decrement in upper airway muscle activity with consequent failure of the pharyngeal dilator muscles to oppose the collapsing pressure that is generated by the diaphragm and accessory muscles during inspiration. The causes of upper airway obstruction during sleep are multi-factorial but there is evidence implicating intrinsic upper airway muscle function and impaired central regulation of the upper airway muscles in the pathophysiology of OSA. The condition is associated with episodic hypoxia due to recurrent apnoea.

Probing the differential effects of infrared light sources IR1072 and IR880 on human lymphocytes: evidence of selective cytoprotection by IR1072.

Light therapy, both laser and LED, have been shown to provide clinical benefit in many therapeutic arenas. The effects of IR1072 and IR880 were investigated, using a range of single and multiple irradiation protocols, for their effect on freshly prepared human lymphocytes stimulated with phytohemagglutinin. Viable cell numbers remained significantly higher after irradiation with IR1072 and were significantly lower after IR880 irradiation compared to untreated controls, following a daily single irradiation over a 5-day period.

A 1.3 kb promoter fragment confers spatial and temporal expression of utrophin A mRNA in mouse skeletal muscle fibers.

Upregulation of utrophin in muscle is currently being examined as a potential therapy for Duchenne muscular dystrophy patients. In this context, we generated transgenic mice harboring a 1.3 kb human utrophin A promoter fragment driving expression of the lacZ gene.

Detailed analysis of the behavior of Lister and Wistar rats in anxiety, object recognition and object location tasks.

The present study, examines some issues in the measure and analysis of behavior in animals. Two strains of rats of both genders were used to illustrate and discuss these issues. We examined to what extent various behavioral measures reflect different or identical emotional or cognitive factors and, how sensitive are the various parameters of a task to differences between strains and genders.

Chronic intermittent asphyxia increases platelet reactivity in rats.

Sleep-disordered breathing is associated with chronic intermittent asphyxia and with a variety of cardiovascular abnormalities. Cardiovascular morbidity and mortality are linked to altered platelet function, and platelet function is affected in sleep-disordered breathing. As there is evidence that chronic continuous hypoxia may alter platelet number and function, the aim of the present study was to test the hypothesis that chronic intermittent asphyxia affects platelet count, activation and aggregation.

Simultaneous recording of breathing and respiratory related neuronal activity in the brainstem of conscious rats.

One aim of integrative neurophysiology is to understand the relationship between neuronal activity and normal evolution of other physiological parameters. In this respect, anaesthetics or paralyzing agents, that have been shown to have a significant effect on several vital physiological processes, can be seen as a real problem for the interpretation of observations. Eletrophysiological recording in awake animals avoids this problem.

Intravascular thrombosis after hypoxia-induced pulmonary hypertension: regulation by cyclooxygenase-2.

Background: Pulmonary hypertension induced by chronic hypoxia is characterized by thickening of pulmonary artery walls, elevated pulmonary vascular resistance, and right-heart failure. Prostacyclin analogues reduce pulmonary pressures in this condition; raising the possibility that cycloxygenase-2 (COX-2) modulates the response of the pulmonary vasculature to hypoxia.

Methods And Results: Sprague-Dawley rats in which pulmonary hypertension was induced by hypobaric hypoxia for 14 days were treated concurrently with the selective COX-2 inhibitor SC236 or vehicle.

Structural and functional analysis of the differential effects of c-Jun and v-Jun on prolactin gene expression.

The protooncogene c-Jun and its oncogenic isoform v-Jun are members of the activator protein 1 family of transcription factors that have been shown to have differential transcriptional effects that are both promoter specific and cell type specific. Previously, we have demonstrated that whereas c-Jun inhibits pituitary-specific rat prolactin (rPRL) promoter activity, expression of v-Jun stimulates the rPRL promoter in GH4 pituitary cells. In this report, we have conducted an extensive structure-function analysis of c-Jun vs.

Effects of chronic intermittent asphyxia on haematocrit, pulmonary arterial pressure and skeletal muscle structure in rats.

Sleep-disordered breathing in humans is a common condition associated with serious cardiovascular and other abnormalities. The prevalence and pathogenesis of increased haematocrit and pulmonary hypertension is controversial and it has been suggested that these changes only occur in patients who also have daytime continuous hypoxaemia. The hypothesis tested here is that the chronic intermittent hypoxia and asphyxia associated with sleep-disordered breathing causes erythropoiesis and pulmonary hypertension and that this occurs in the absence of periods of continuous hypoxia.

Cord blood units collected at a remote site: a collaborative endeavor to collect umbilical cord blood through the Hawaii Cord Blood Bank and store the units at the Puget Sound Blood Center.

Background: Umbilical cord blood is a useful source of hematopoietic stem cells, especially because compared to equivalent HLA-matched stem cells from unrelated adult donors. A network of community collection sites targeted at particular ethnic groups and serviced by a central processing and storage facility can maximize the genetic diversity of banked cord blood units (CBUs) in a cost-effective fashion.

Study Design And Methods: The present study compared CBUs collected near the Puget Sound Blood Center in Seattle, WA, with those collected in Honolulu, HI, and processed in Seattle.

Upper airway EMG responses to acute hypoxia and asphyxia are impaired in streptozotocin-induced diabetic rats.

Obstructive sleep apnoea (OSA) is a major clinical disorder that is characterised by multiple episodes of upper airway obstruction due to failure of the upper airway dilator muscles to maintain upper airway patency. The incidence of OSA is high in many endocrine disorders including both insulin-dependent and non-insulin-dependent diabetes but the reasons for this are not known. We wished to test the hypothesis that central respiratory motor output to the upper airway muscles is preferentially impaired in a rat model of diabetes mellitus.

Effects of chronic hypobaric hypoxia on contractile properties of rat sternohyoid and diaphragm muscles.

1. Chronic hypoxia occurs in a variety of circumstances, including respiratory disease and exposure to altitude, and is known to affect respiratory muscle structure. However, little is known about its effects on respiratory muscle contractile properties.

The effect of vitamin E on the structure of membrane lipid assemblies.

The effects of vitamin E on the activity of membrane-dependent enzymes suggest that it acts indirectly by modifying some properties of the lipid host. The effects of alpha-tocopherol (alpha-T) and alpha-tocopherol hemisuccinate (alpha-THS) on phospholipid monolayer structure, curvature, and bending elasticity were examined using X-ray diffraction and the osmotic stress method. These ligands were mixed with the hexagonal phase-forming lipid, dioleoylphosphatidylethanolamine (DOPE).

Fibroblast growth factors regulate prolactin transcription via an atypical Rac-dependent signaling pathway.

Fibroblast growth factors (FGFs) play a critical role in pituitary development and in pituitary tumor formation and progression. We have previously characterized FGF signal transduction and regulation of the tissue-specific rat prolactin (rPRL) promoter in GH4 pituitary cells. FGF induction of rPRL transcription is independent of Ras, but mediated by a protein kinase C-delta (PKCdelta)-dependent activation of MAPK (ERK).

Reliability and construct validity for scale of rejection of Christianity.

A sample of 16 male and 30 female undergraduates completed the Greer and Francis Scale of Rejection of Christianity. The data support the internal consistency reliability and construct validity of the scale for this sample.

Selective repression of rat prolactin gene by stable expression of dominant-negative Ets in GH4 pituitary cells.

Members of the Ets family of transcription factors are key regulators controlling prolactin (PRL) gene expression. Utilizing a transient transfection approach and the GH4 rat pituitary cell line, we have shown that Ets- 1 acts synergistically with the pituitary-specific POU homeodomain transcription factor, Pit-1, to mediate basal and Ras-induced regulation of the proximal (-425) rat PRL (rPRL) promoter. Although the transient transfection approach has provided important information regarding rPRL proximal promoter regulation, the role of Ets factors in the regulation of the intact, endogenous PRL promoter has not been explored.

Effects of chronic intermittent asphyxia on rat diaphragm and limb muscle contractility.

Objective: In obstructive sleep apnea (OSA), there is intermittent upper airway (UA) collapse due to an imbalance between the collapsing force generated by the diaphragm and the stabilizing force of the UA muscles. This results in chronic intermittent asphyxia (CIA). We have previously shown that CIA affects UA muscle fatigue, but little is known about the effects of chronic hypoxia on diaphragm or on limb muscle contractile properties and structure.

Attitudes to long-term care in multiple sclerosis.

At a recent conference workshop, a group of specialist nurses examined their attitudes towards individuals with multiple sclerosis moving into long-term care. This article summarises how the group members examined their attitudes, the literature reviewed and what was learnt by sharing experiences. It also suggests how nurses could promote positive attitudes towards, and ease, the transition of patients into long-term residential care.

The prognostic value of the components of the Glasgow Coma Scale following acute stroke.

Background: The Glasgow Coma Scale (GCS) is widely used in assessing level of consciousness. The GCS verbal component may be misleading in acute stroke: a focal neurological deficit leading to dysphasia could affect the score, independently of level of consciousness.

Aim: To investigate the relationship, in all strokes and in dysphasic patients, between stroke outcome and total GCS (with and without the verbal score) and its components, to assess their relative values.