Sildenafil citrate improves sperm motility but causes a premature acrosome reaction in vitro

Objective: to determine if sildenafil citrate; a cyclic monophosphate specific type 5 phosphodiesterase inhibitor, influences sperm motility or the acrosome reaction. Design: laboratory analysis of sperm motility after exposure to sildenafil citrate using computer assisted semen analysis (CASA) and acrosome reaction by fluoroscein isothiocyanate labelled peanut agglutinin (FITC-PNA) staining. Setting: An ART unit Patients: 57 male patients Interventions: Sperm were divided into 90% (the best fertilizing potential used in assisted conception) and 45% (the poorer subpopulation) fractions by density centrifugation and incubated with sildenafil citrate ( 0.67uM) at 37ï?°C for up to 180 minutes. Main outcome measures: both the numbers and velocity of progressively motile sperm were significantly increased by sildenafil citrate between 15 and 135 minutes. Further, samples revealed that these effects were consistent in the 90% and 45% subpopulations of sperm. In both subpopulations, sildenafil also caused a significant increase in the proportion of acrosome reacted sperm - 22.1% compared with 11.8% in the control group of the good quality fraction (p

Implementing a resuscitation policy for patients at the end of life in an acute hospital setting: qualitative study

Objective : To explore attitudes and experiences of doctors and nurses regarding cardiopulmonary resuscitation for patients with end stage illness in an acute hospital. Design : Qualitative study; thematic analysis of two audio-taped focus groups and four semi-structured interviews. Setting : Acute district hospital, Northern Ireland. Participants : Seven nurses and nine doctors; varying nationality, gender and years of professional experience; involved in cardiopulmonary resuscitation decision-making. Results : Participants reported different interpretations of resuscitation policy and of what do not attempt to resuscitate (DNAR) decisions meant in relation to practical care for patients. This confusion in translating policy into practice contributed to communication difficulties in initiating, documenting and implementing cardiopulmonary resuscitation decisions. Participants were aware of how clinical conditions could change and reported uncertainty in determining end stage illness; they expressed fears of potential consequences of DNAR decisions for patients' care. The more disease-centred approach of doctors to patients' management, compared to nurses' more patient-centred approach, contributed to inter-professional conflict within teams. Doctors identified training needs in applying resuscitation policy and ethical principles in `real life' and nurses identified a need for ongoing professional support, which was perceived as being less available to junior doctors. Personal relationships between staff and patients, cultural reluctance to address sensitive issues and local community expectations of relatives being involved in decisions added to policy implementation difficulties. Conclusions : The findings indicate a need for ongoing staff support and training in applying resuscitation policy to decisions for patients with end stage illness in an acute hospital. They support suggestions that reviews of local resuscitation policy and of national guidelines should be undertaken with openness and honesty regarding the goals, opportunities and difficulties involved in trying to deliver good end of life care in local settings. Palliative Medicine 2007; 21 : 305—312 Key Words: do not attempt resuscitation (DNAR) • end stage illness • inter-professional • policy • resuscitation decisions

Development of composite tissue scaffolds containing naturally sourced mircoporous hydroxyapatite

The aims of this work were to investigate the conversion of a marine alga into hydroxyapatite (HA), and furthermore to design a composite bone tissue engineering scaffold comprising the synthesised HA within a porous bioresorbable polymer. The marine alga Phymatolithon calcareum, which exhibits a calcium carbonate honeycomb structure, with a natural architecture of interconnecting permeable pores (microporosity 4-11 mu m), provided the initial raw material for this study. The objective was to convert the alga into hydroxyapatite while maintaining its porous morphology using a sequential pyrolysis and chemical synthesis processes. Semi-quantitative XRD analysis of the post-hydrothermal material (pyrolised at 700-750 degrees C), indicated that the calcium phosphate (CaP) ceramic most likely consisted of a calcium carbonate macroporous lattice, with hydroxyapatite crystals on the surface of the macropores. Cell visibility (cytotoxicity) investigations of osteogenic cells were conducted on the CaP ceramic (i.e., the material post-hydrothermal analysis) which was found to be non-cytotoxic and displayed good biocompatibility when seeded with MG63 cells. Furthermore, a hot press scaffold fabrication technique was developed to produce a composite scaffold of CaP (derived from the marine alga) in a polycaprolactone (PCL) matrix. A salt leaching technique was further explored to introduce macroporosity to the structure (50-200 mu m). Analysis indicated that the scaffold contained both micro/macroporosity and mechanical strength, considered necessary for bone tissue engineering applications. (C) 2008 Published by Elsevier B.V.

Objective assessment of cardiopulmonary resuscitation skills of 10-11 year-old schoolchildren using two different external chest compression to ventilation ratios

Study which shows that 10-11 yr olds are capable of effective CPR after a single 2 hour training session using the ABC for Life programme. However they perfrom more effective CPR when using a ratio of 15:2 rather than 30:2 chest compressions : ventilations