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A Neill

Publications and source records attributed to A Neill.

9 recordsLinked to original sources
PubMed2005

Pretransplant islet culture: a comparison of four serum-free media using a murine model of islet transplantation.

INTRODUCTION: Human islet transplant protocols frequently incorporate a brief period of islet culture before transplantation. The optimal medium for pretransplant islet culture is unknown. METHODS: We compared four serum-free media formulated for human islets: Miami (MM1), Memphis (M-SFM), Edmonton (EDM), and hCell OCZEM-SF/AF (hCell). Islets isolated from a single human pancreas with purity >80% were cultured in 2500-islet-equivalent (IE) fractions using the media listed. After 7 days, each 2500-IE fraction was grafted under the kidney capsule of a streptozocin-diabetic rag1 mouse (n = 4 per group). Mice were evaluated with serum glucose monitoring, stimulated C-peptide release, and glucose tolerance tests. Islet fractions transplanted immediately after isolation (n = 4 mice) served as controls. In vitro islet function was assessed on days 0 and 3 and included insulin release (after static glucose stimulation), total cellular C-peptide content, cell count, and viability. RESULTS: Glucose control was improved in all cohorts of mice after transplant, but only islet grafts cultured in MM1 were statistically indistinguishable from fresh islets. MM1- and hCell-cultured islet grafts showed improved glucose tolerance compared with fresh islets; C-peptide release was similar among the four cohorts. In vitro, only islets cultured in MM1 had similar stimulation index to fresh islets, whereas only hCell- and MM1-cultured islets demonstrated recovery of C-peptide content and insulin release. CONCLUSIONS: Media choice before transplant can influence islet quality, even when culture periods are short. Miami MM1 and hCell media may provide better islet protection than alternative media.

Animals↗
PubMed2002

Sleep disorders: a potential role in New Zealand motor vehicle accidents.

BACKGROUND: The potential role of sleep disorders in New Zealand motor vehicle accidents (MVA) has not been systematically studied. AIMS: To trial a recruitment method and document the frequency of sleep disorders in drivers attending an emergency department with injury following MVA. METHODS: Injured drivers admitted to Wellington Hospital Emergency Department were prospectively recruited by letter and follow-up telephone call. Data from a traffic accident, health and sleep questionnaire and polysomnography were collected and analysed using the SPSS statistical package. RESULTS: Of 120 eligible drivers, 40 (33%) completed the study protocol. The mean age of participants was 44 +/- 17 years. Non-participants were younger (mean age 33 +/- 14 years, P < 0.01) and more often of Asian or Pacific Island ethnicity (P < 0.01). Twenty-seven (67%) felt unrefreshed on waking and 10 (25%) had an elevated Epworth Sleepiness Score (> 10/24). Six (15%) felt drowsy or fell asleep prior to the accident. Sleep disorders were common (40%): obstructive sleep apnoea 14 (35.9%), periodic limb movements of sleep three (7.7%), sleep restriction (< 6 h sleep on a regular basis) five (12.5%), and insomnia one (2.5%). CONCLUSIONS: Daytime somnolence and sleep disorders were commonly found in drivers attending the Emergency Department after accidents resulting in injury. Driver fatigue and sleep disorders should be considered as a potential contributing factor in New Zealand MVAs. Recruitment of drivers following a MVA via the Emergency Department is challenging. Strategies to improve recruitment are discussed.

Accidents, Traffic↗
PubMed2000

Shoulder dystocia.

Explore the source record for details and available documents.

Journal Article↗
PubMed2000

Three nursing home outbreaks of Norwalk-like virus in Brisbane in 1999.

We report on three nursing home outbreaks of gastroenteritis in Brisbane in 1999. The presence of Norwalk-like virus (NLV) genogroup 2 was demonstrated by reverse transcription polymerase chain reaction (RT-PCR) in all three outbreaks. Common findings of these investigations were rapid spread of the illness within the institutions and difficulties in identifying a common source. Nursing home populations are vulnerable and it is important for each institution to have infection control policies in place so outbreaks can be managed promptly. This includes the exclusion of ill staff for 48 to 72 hours after recovery from illness. Genogrouping of NLV by RT-PCR can take several days so control measures will generally have to be instituted before results become available.

Adult↗
PubMed1997

Comparison of effects of sustained isocapnic hypoxia on ventilation in men and women.

Sleep-related respiratory disturbances are more common in men than in premenopausal women. This might, in part, be due to different susceptibilities to the respiratory depressant effects of hypoxia. Therefore, we compared ventilation during 10 min of baseline room-air breathing and 20-min sustained isocapnic hypoxia (fractional inspired O2 = 11%, arterial saturation of O2 approximately 80%) followed by 10 min of breathing 100% O2 in 10 normal men and in 10 women in the follicular phase of the menstrual cycle. Control measurements were made during two transitions from room air (10 min) to 100% O2 (10 min) and averaged. Inspired minute ventilation (VI) after 2 min of hypoxia was the same in men and women [131 +/- 6.1% baseline for men, 136 +/- 7.7% baseline for women; not significant (NS)] and declined to the same level after 20 min (115 +/- 5.0% baseline for men, 116 +/- 6.6% baseline for women; NS) associated with a similar decline in inspiratory time and tidal volume. Breathing frequency did not change. VI decreased transiently during subsequent 100% O2 breathing in both men and women, associated with reduced frequency and duty cycle and increased expiratory time. The fall in VI was significantly greater than that observed during control hyperoxia experiments in men but not in women. We conclude that ventilatory responses to sustained isocapnic hypoxia do not differ between awake healthy men and women in the follicular phase of their menstrual cycle. However, after termination of isocapnic hypoxia, men appear to depress their ventilation to a greater degree than women.

Adult↗
PubMed1996

Pressure-limited ventilation with permissive hypercapnia and minimum PEEP in saline-lavaged rabbits allows progressive improvement in oxygenation, but does not avoid ventilator-induced lung injury.

OBJECTIVE: To determine whether pressure-limited intermittent mandatory ventilation with permissive hypercapnia and positive end-expiratory pressure (PEEP) titrated to arterial oxygen tension (PaO2) prevents or reduces acute lung injury, compared to conventional ventilation, in saline-lavaged rabbits. DESIGN: Prospective randomised trial. SETTING: University animal laboratory. SUBJECTS: 18 New Zealand White rabbits. INTERVENTIONS: Following five sequential saline lung lavages, anaesthetised rabbits were randomly allocated in pairs to receive either of two ventilation protocols using intermittent mandatory ventilation. The study group had peak inspiratory pressure limited to 15 cm H2O and arterial partial pressure of carbon dioxide (PaCO2) was allowed to rise. The control group received 12 ml/kg tidal volume with rate adjusted for normocarbia. PEEP and fractional inspired oxygen (FIO2) were adjusted to maintain, PaO2 between 8 and 13.3 kPa (60 and 100 mm Hg) using a predetermined protocol. At 10 h or following death, lung lavage was repeated and lung histology evaluated. MEASUREMENTS AND MAIN RESULTS: The mean increase in lavage cell counts and protein concentration and hyaline membrane scores were not significantly different between the groups. Oxygenation progressively improved more in the study group (p = 0.01 vs control for PaO2/FIO2 ratio and alveolar-arterial oxygen tension gradient (AaDO2)). PEEP was similar and the mean airway pressure higher in the control group, suggesting that this probably resulted from less ventilator-induced injury in the study group. Four deaths occurred in the control group (three due to pneumothorax and one to hypoxaemia) and none in the study group (p = 0.08). CONCLUSIONS: This ventilatory protocol may have failed to prevent lung overdistension or it may have provided insufficient PEEP to prevent injury in this model; PEEP greater than the lower inflection point of the pressure-volume curve has been shown to prevent injury almost entirely.

Animals↗
PubMed1994

Plasma brain natriuretic peptide in assessment of acute dyspnoea.

Recognition of heart failure (HF) may be difficult in patients presenting with acute dyspnoea, particularly in the presence of chronic airways obstruction. Since increased secretion of the cardiac hormones atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP) occurs early in the course of HF, we have assessed the value of measuring these hormones in plasma in the diagnosis of suspected HF in 52 elderly patients presenting with acute dyspnoea, and compared values with left-ventricular ejection fraction (LVEF), a standard measure of left-ventricular function, by radionuclide angiography. Patients were enrolled prospectively. On the basis of clinical findings, conventional tests, and response to specific treatment, 20 of the 52 patients were classified as having primary lung disorder (PLD), 12 as HF alone, and 20 as HF with underlying PLD (HF/PLD). Compared with findings in PLD patients, LVEF was significantly depressed in HF and HF/PLD patients (p < 0.001), whereas both plasma ANP and BNP were significantly increased (p < 0.001). Admission plasma BNP concentration more accurately reflected the final diagnosis of HF (93% sensitivity and 90% specificity when BNP > or = 22 pmol/L) than LVEF or plasma ANP concentration. When all patients were considered together, there were strong negative correlations between LVEF and log BNP (r = -0.7, p < 0.001) and log ANP (r = -0.59, p < 0.001). Our finding that plasma BNP is raised in dyspnoeic patients with HF but not in acutely breathless patients with PLD, suggests that rapid BNP assays may assist in the diagnosis of patients with acute dyspnoea.

Acute Disease↗
PubMed1984

Formation of a direct arterial blood supply to the anterior pituitary gland following complete or partial interruption of the hypophyseal portal vessels.

If regions of the anterior pituitary gland received systemic blood via a direct arterial blood supply these regions would escape hypothalamic regulation and thus be a sequela in endocrine disorders. Since, in the untreated rat, all of the blood supply to the anterior pituitary gland is via the hypophyseal portal vessels, we hypothesized that partial interruption of the portal vessels could provoke the establishment of a direct arterial blood supply (arteriogenesis). We utilized the injection of polystyrene microspheres (15 or 9 micron diameter) into the left ventricle of the heart to test this hypothesis. Microspheres are trapped in the first capillary plexus they reach since they are too large to traverse the capillaries. No microspheres reached the anterior pituitary gland of control rats, a finding consistent with the fact that the anterior pituitary gland receives all of its blood supply via the hypophyseal portal blood vessels. Microspheres were observed in the primary portal capillary plexus in the infundibulum (median eminence), infundibular stalk (pituitary stalk), and infundibular process (pars nervosa), the first capillary plexus which they reached. A lesion of the medial basal hypothalamus (MBH) which destroyed the long portal vessels did not result in arteriogenesis since few, if any, microspheres were observed in the anterior pituitary gland. We confirmed, using vascular casts, that these lesions resulted in the long-term destruction of the primary portal capillaries in the infundibulum and of the long portal vessels. In MBH-lesioned animals it appears that all of the blood supply of the anterior pituitary gland is via short portal vessels arising from the infundibular stem and process.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗