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Notes: Motoneuron dependence on target-derived trophic factors during development is well established, with loss of trophic support leading to the death of these cells. A complete understanding of the intracellular signal transduction machinery associated with extracellular survival signals requires the examination of individual pathways in various cellular and environmental contexts. In cells deprived of trophic support, and hence compromised for survival, phosphoinositide-3-kinase (PI3K) is decreased when compared with healthy cells supplied with trophic support. Extracellular signal-regulated kinase 1/2 (ERK1/2) signaling is dramatically decreased in deprived cells. We have examined the role of these two pathways to understand how changes in their activity regulate motoneuron survival and death. Pharmacological inhibition of PI3K attenuated motoneuron survival and was important in the regulation of Bcl-2 serine phosphorylation, limited release of cytochrome c into the cytoplasm and caspase activation. Bax translocation from cytoplasm to mitochondria was not altered when PI3K was inhibited. High levels of ERK1/2 inhibition robustly attenuated motoneuron survival in cells supplied with trophic support, whereas moderate inhibition of ERK1/2 activation had little effect. ERK1/2 inhibition in these cells decreased Bcl-2 phosphorylation and resulted in release of cytochrome c from the mitochondria. Bax translocation and caspase activation were not affected by ERK1/2 inhibition. These data reveal that changes in PI3K and ERK1/2 signaling lead to individual and overlapping effects on the cell-death machinery. Characterizing the role of these pathways is critical for a fundamental understanding of the development and degeneration of specific neuronal populations.

Notes: Objective  To assess whether outpatient hysteroscopy using the ‘no-touch’ technique confers any advantages in terms of patient discomfort over the traditional technique.Design  Prospective randomised controlled study.Setting  Outpatient hysteroscopy clinic in a large university undergraduate teaching hospital.Population  All women referred for outpatient hysteroscopy in a 12-month period.Interventions  Women were randomised to undergo either traditional saline hysteroscopy requiring the use of a speculum and tenaculum, or a ‘no-touch’ vaginoscopic hysteroscopy which does not require a speculum or tenaculum. Each group was further subdivided to have hysteroscopy with either a 2.9-mm or 4-mm hysteroscope. Patients were asked to complete pre- and postprocedure questionnaires ranking pain scores.Main outcome measures  The relative success of each of these techniques, requirement for local anaesthetic and pain scores at different times during the hysteroscopy were recorded at the end of the procedure. The time taken to carry out each procedure was also measured.Results  One hundred and twenty women were recruited in this study: 60 were randomised to traditional hysteroscopy and 60 to ‘no-touch’ hysteroscopy. The overall success rate for hysteroscopy was 99%. There was no significant difference in the requirement for local anaesthetic between the two groups, but those who underwent ‘no-touch’ hysteroscopy with a 2.9-mm hysteroscope had the lowest requirement of local anaesthetic (10% compared with 27% in the no-touch hysteroscopy with a 4-mm hysteroscope group). The time taken to perform hysteroscopy and biopsy was significantly shorter with ‘no-touch’ hysteroscopy (5.9 vs 7.8 min; difference 1.9, 95% CI 0.7–3.1). There were no differences in pain scores between the groups at different times during hysteroscopy.Conclusions  ‘No-touch’ or vaginoscopic hysteroscopy is significantly faster to perform than the traditional technique. Although there was no difference in pain scores between the two techniques, local anaesthetic requirements were least in those who underwent ‘no-touch’ hysteroscopy with a narrow bore hysteroscope.

Notes: Objectives  To evaluate triple tourniquets in controlled conditions and for the first time to investigate the hypothesis that leaving a semi-permanent tourniquet around the uterine artery reduces post-operative bleeding from the uterine incisions.Design  A randomised controlled trial.Setting  Two University teaching hospitals.Population  Twenty-eight patients with symptomatic fibroids and uterine sizes ranging from 14 to 24 weeks of gestation undergoing open myomectomy.Methods  A number 1 polyglactin suture was tied around the cervix to occlude the uterine arteries, and polythene tourniquets were tied around the infundibulopelvic ligament to obstruct the ovarian vessels. At the end of the procedure, the ovarian ties were released but the uterine artery suture remained in situ.Main outcome measures  Intra-operative blood loss, post-operative blood loss, blood transfusion rates, operative morbidity, uterine blood flow and ovarian function.Results  There was significantly less blood lost in the tourniquet group than in the control group (difference between means 1870 mL, 95% CI 1159–2580 mL, P 〈 0.0001; transfusion rates of 7% and 79%, P= 0.0003). The volume in the pelvic drain 20 min post-operatively and after 48 hours failed to reach statistical significance between the two groups (P= 0.10 and P= 0.165). There were no differences in uterine artery Doppler resistance indices at five days (P= 0.54), six weeks (P= 0.47), three months (P= 0.49) and at six months (P= 0.18). Day two serum FSH concentrations after surgery were unchanged (P= 0.45), compared with baseline values.Conclusions  Triple tourniquets are effective in reducing bleeding and transfusion rates. There appears no obvious adverse effect on uterine perfusion or ovarian function.

Notes: Fresh beef was stored in mixtures of carbon dioxide and oxygen, and measurements were made of gas exchanges and colour of the meat. Oxygen and carbon dioxide dissolved in the meat, while respiration consumed oxygen and produced more carbon dioxide. The subsequent reductions in oxygen and carbon dioxide partial pressures depended to some extent on the packaging operation and, under commercial conditions, could reach critical levels. At high oxygen partial pressures the layer of oxygenated tissue at the surface was sufficient to conceal the development of underlying metmyoglobin which causes discolouration in conventionally pre-packaged meat. Although this layer was oxidized slowly to metmyoglobin, meat packed in 80% O2 and 20% CO2 remained attractive for at least a week at + 1°C.

Notes: Pig sides were cooled to 0°C at two different rates and the amount of drip from joints after storage for two days at 0°C was estimated. Drip accurred according to an anatomical distribution pattern which was unaffected by cooling rate and breed, the greatest loss being from the loin and leg joints. The quicker cooling rate consistently limited the amount of drip, regardless of breed. This was demonstrated using whole carcasses, leg joints and individual muscles. Pigs whose pH fell rapidly after slaughter tended to give joints with high drip loss but, even with these, the effect of quicker cooling was still observed.

Notes: A 7-year-old girl underwent laser ablation of tonsillar remnants. Following the procedure, which was surgically uncomplicated, the laser resistant tracheal tube used could not be removed; it was firmly lodged in the larynx, immediately below the glottic opening. This case highlights the importance of careful selection of laser resistant tracheal tubes for use in paediatric patients and challenges traditional concepts of paediatric upper airway anatomy.

Notes: Lamb carcasses were chilled rapidly and slowly under controlled conditions and the texture of the meat examined after cooling and after conditioning at 0°C. Sensory and objective measurements of texture showed that the rapid chilling rate induced toughness in normal lamb carcasses. Texture was in all cases significantly improved by conditioning, but the rapidly chilled samples remained undesirably tough. The tenderizing effect of conditioning was measurable by both sensory and mechanical assessments of texture, but the changes in sarcomere length were only marginal.