Ultrastructural and metabolic studies of isolated and cultured hepatocytes

Cells isolated from adult rat liver form distinct cell populations: the parenchymal cells or hepatocytes and the non-parenchymal cells, mainly endothelial and Kupffer cells. These two groups are easy to separate by centrifugation methods, including centrifugal elutriation. The single-cell suspension of hepatocytes seems to be constituted of subfractions which are located roughly in the centrilobular and perilobular regions of the liver lobule and are differentiated so that they form cell lines with distinct metabolic activities. The basic means of characterizing the isolated hepatocytes consists of determining their size distribution, their sedimentation and elutriation properties, and their metabolic activities. Cultures of hepatocytes offer the possibility of prolonging their survival and of studying the differentiation of new bile canaliculi and the reconstitution of biliary polarity in the cytoplasm. The combination of Kupffer cells with hepatocytes improves the culture condition, as a result of elimination of cell debris by phagocytosis by the non-parenchymal cells. The application of the isolation and partition methods to pre-neoplastic liver allows us to classify the cells according to their degree of hyperplasia and opens up a new field of investigation.

Ossification of the infraspinatus tendon-bursa in 13 dogs

Ossification of the infraspinatus tendon-bursa was diagnosed in 13 labrador retrievers, 12 of which were lame in one thoracic limb and the other in both. They ranged in age from 28 to 121 months (mean 69.4 months). The lameness developed gradually and was progressive in 11 of the 14 affected joints. Scapular muscle atrophy and signs of pain on direct pressure over the infraspinatus tendon of insertion were key clinical signs. Caudocranial radiographs revealed multiple mineralised masses lateral to the proximal humerus or glenohumeral joint in 11 of the 26 joints and single masses in 12. An arthroscopic examination revealed concomitant ligament or tendon abnormalities in six of seven shoulders. The dogs were followed up from one to 55 months (mean 20 months). Of five shoulders treated with non-steroidal anti-inflammatory drugs (nsaids), one resolved, two improved and two were managed surgically. Of six shoulders treated by the injection of long-acting intra-articular corticosteroid (five before and one after surgery), three resolved, two improved and one was unchanged. Of six shoulders treated by the surgical resection of the infraspinatus tendon and bursa (three before and two after treatment with nsaids, and one after treatment with a long-acting intra-articular corticosteroid), four improved, one was unchanged and one was managed with an intra-articular long-acting corticosteroid. One shoulder was managed by restricted exercise and the lameness resolved. Histological examination of the excised tissues revealed heterotopic bone within the infraspinatus tendon and/or bursa.

IGF-1 receptor signalling determines the mitogenic potency of insulin analogues in human smooth muscle cells and fibroblasts

AIMS/HYPOTHESIS

Mitogenic activity of insulin and insulin analogues and the involvement of the IGF-1 receptor (IGF-1R) is still a controversial issue. We compared levels of the proteins IGF-1R and insulin receptor (InsR) in fibroblasts and smooth muscle cells from healthy donors and assessed the downstream signalling and growth-promoting activity of insulin and insulin analogues.

METHODS

DNA synthesis was monitored in human fibroblasts and coronary artery smooth muscle cells. Using small interfering RNAs, the levels of IGF-1 and InsR were reduced by 95 and 75%, respectively.

RESULTS

Enhanced mitogenic potency of insulin and insulin analogues was observed which correlated with increased levels of IGF-1R and/or IRS-1. A reduction in the IGF-1R level significantly blunted stimulation of Akt phosphorylation by IGF-1, AspB10 and glargine by 72, 58 and 40%, respectively. Akt phosphorylation in response to insulin remained unaffected. Silencing of InsR did not significantly alter Akt phosphorylation in response to IGF-1, AspB10 and glargine. IGF-1R knockdown reduced the stimulation of DNA synthesis in response to IGF-1 and glargine to a level identical to that produced by insulin.

CONCLUSIONS/INTERPRETATION

These data show a prominent role of IGF-1R/Akt signalling in mediating the mitogenic effects of insulin analogues. Regular insulin stimulates DNA synthesis by exclusively activating InsR, whereas insulin analogues mainly signal through IGF-1R. It is suggested that inter-individual differences in the levels of proteins of the IGF-1R system may function as a critical determinant of the mitogenic potency of insulin analogues.

A systematic literature review of the effectiveness of non-pharmacological interventions to prevent wandering in dementia and evaluation of the ethical implications and acceptability of their use

OBJECTIVES

To determine the effectiveness and cost-effectiveness of non-pharmacological interventions (excluding subjective barriers) in the prevention of wandering in people with dementia, in comparison with usual care, and to evaluate through the review and a qualitative study the acceptability to stakeholders of such interventions and identify ethical issues associated with their use.

DATA SOURCES

Major electronic databases were searched up until 31 March 2005. Specialists in the field.

REVIEW METHODS

Selected studies were assessed and analysed. The results of two of the efficacy studies that used similar interventions, designs and outcome measures were pooled in a meta-analysis; results for other studies which reported standard deviations were presented in a forest plot. Owing to a lack of cost-effectiveness data, a modelling exercise could not be performed. Four focus groups were carried out with relevant stakeholders (n = 19) including people with dementia and formal and lay carers to explore ethical and acceptability issues in greater depth. Transcripts were coded independently by two reviewers to develop a coding frame. Analysis was via a thematic framework approach.

RESULTS

Ten studies met the inclusion criteria (multi-sensory environment, three; music therapy, one; exercise, one; special care units, two; aromatherapy, two; behavioural intervention, one). There was no robust evidence to recommend any non-pharmacological intervention to reduce wandering in dementia. There was some evidence, albeit of poor quality, for the effectiveness of exercise and multi-sensory environment. There were no relevant studies to determine the cost-effectiveness of the interventions. Findings from the narrative review and focus groups on acceptability and ethical issues were comparable. Exercise and distraction therapies were the most acceptable interventions and raised no ethical concerns. All other interventions were considered acceptable except for physical restraints, which were considered unacceptable. Considerable ethical concerns exist with the use of electronic tagging and tracking devices and physical barriers. Existing literature ignores the perspectives of people with dementia. The small number of participants with dementia expressed caution regarding the use of unfamiliar technology. Balancing risk and risk assessment was an important theme for all carers in the management of wandering.

CONCLUSIONS

There is no robust evidence so far to recommend the use of any non-pharmacological intervention to reduce or prevent wandering in people with dementia. High-quality studies, preferably randomised controlled trials, are needed to determine the clinical and cost-effectiveness of non-pharmacological interventions that allow safe wandering and are considered practically and ethically acceptable by carers and people with dementia. Large-scale, long-term cohort studies are needed to evaluate the morbidity and mortality associated with wandering in dementia for people both in the community and in residential care. Such data would inform future long-term cost-effectiveness studies.

A technique for the measurement of renal ATP in a large animal model of septic shock

BACKGROUND

The mechanisms responsible for acute renal failure in sepsis are not understood. Measurement of tissue ATP might help to understand this process but, in the large animal, it is hampered by major technical difficulties.

OBJECTIVE

To develop a technique to monitor ATP in the kidney of a large mammal during the induction of septic shock and then circulatory arrest.

METHODS

Implantation of a custom-made phosphorus coil around the left kidney. Induction of septic shock by intravenous E. coli administration. Acquisition of 31 P magnetic resonance (MR) spectroscopic data at 3-tesla before and during septic shock over several hours. Induction of euthanasia and measurement of the same 31 P signal immediately and thirty minutes after circulatory arrest.

RESULTS

Clear reproducible 31 P MR spectra were obtained before and after the induction of septic shock and euthanasia. They indicated limited changes in ATP during septic shock. An expected rapid and dramatic decrease in ATP occurred with euthanasia.

CONCLUSIONS

It is possible to sequentially monitor renal bioenergetics in a large mammal during septic shock using an implanted custom-made phosphorus coil and 3-tesla MR technology. This technique offers a novel approach to the investigation of septic renal failure.

Corticosteroids in infant chronic lung disease

Chronic lung disease (CLD), defined as chronic oxygen dependency at 36 weeks postmenstrual age, is increasing and associated with chronic respiratory morbidity and high health care utilisation at follow up. Many strategies, tested in randomised trials, have failed to reduce CLD. In contrast, corticosteroids if given systemically within the first two weeks after birth reduce CLD and may also favourably influence survival. Unfortunately, systemically administered corticosteroids have many acute side-effects and adversely affect long term neurodevelopmental outcome. If given by inhalation, corticosteroids have fewer adverse effects, but are less efficacious. Further research is required to accurately identify infants at highest risk of developing CLD, the corticosteroid dosage associated with a positive risk: benefit ratio and preferably a safer and more effective alternative therapy.

Pantarsal arthrodesis with a customised medial or lateral bone plate in 13 dogs

Pantarsal arthrodesis was performed in 12 dogs using a customised medial bone plate, and in one using a lateral bone plate. The dogs' ages ranged from 14 months to 144 months (median 30 months) and their bodyweights ranged from 7 to 66 kg (median 32 kg). Before the surgery they had been lame on a pelvic limb for between one and 16 months (median eight months). In eight of the dogs the fixation of the plate was augmented with a calcaneotibial positional screw, and in one of them with a talocrural lag screw. A cranial half cast was applied to 12 of the dogs and an external skeletal fixator to the other for six to eight weeks. Five complications were recorded in four of the dogs. Between 29 and 156 weeks postoperatively the clinical outcome was graded as excellent in six dogs, good in six dogs and fair in the other.

Emergency department management and outcome for self-poisoning: a cohort study

Self-poisoning in adults is an important public health problem across the world, but evidence to guide psychological management is lacking. In the current cohort study we wished to investigate whether aspects of routine Emergency Department management such as receiving a psycho-social assessment, or being referred for specialist follow up, affected the rate of repetition of self-poisoning. The study was carried out in four inner city hospitals in Greater Manchester, United Kingdom, over a 5-month period. We used hospital information systems and reviewed the case notes of every patient presenting to the Emergency Department to identify prospectively all adult patients presenting with deliberate self-poisoning. Data regarding the Emergency Department management of each episode were collected. The Manchester and Salford self-harm database was used to determine the number of individuals who went on to repeat self-poisoning within 6 months of their index episode. During the recruitment period 658 individuals presented with self-poisoning. Traditional risk factors for repetition such as substance dependence, psychiatric contact, and previous self-poisoning were associated with a greater likelihood of receiving a psycho-social assessment or being referred for specialist follow-up. Ninety-six patients (14.6%) repeated self-poisoning within 6 months of their index episode. After adjustment for baseline demographic and clinical characteristics and hospital, receiving a psycho-social assessment was not associated with reduced repetition but being referred for specialist follow-up was [adjusted hazard ratio for repetition (95% CI): 0.49 (0.25 to 0.84), P=.01]. We found that being referred for active follow-up after self-poisoning was associated with a reduced risk of repetition. The implications of this finding are discussed. Further studies using both cohort and randomized controlled study designs will help inform management strategies for patients who poison themselves.

Lessons from the implementation of a home telecare service

We conducted a qualitative evaluation of the introduction of a telenursing service. The service used an analogue videophone linked with a physiological monitoring device, which allowed the transmission of data between the patient's home and the hospital. A researcher kept a detailed diary of day-to-day activity for the first year of the project. Computer software for qualitative data analysis was used to code the text and the analysis followed the principles of constant comparison. The diary entries documented how the commercially available equipment was adapted to suit the organization and content of the nurses' work. The nurses made a number of suggestions to improve the user-friendliness of the equipment. The technology, the existing home care service (the comparison arm of the study) and the randomized controlled trial itself all underwent continuous change. The traditional randomized control design of trial has limitations in this situation, and there is a need for more realistic trial designs.

Service provision and outcome for deliberate self-poisoning in adults--results from a six centre descriptive study

BACKGROUND

The aim of the study was to compare the hospital management and direct costs of self-poisoning in six United Kingdom hospitals and to investigate whether hospital management influences outcome.

METHOD

This was a prospective descriptive study carried out at three teaching hospitals and three district general hospitals in North West England on adults (aged 16 or over) presenting to the study centres with deliberate self-poisoning over a 5-month period. Data were based on demographic and clinical characteristics, management of the current episode, direct costs and repetition of self-poisoning within 12 weeks of index episode.

RESULTS

There were 1778 episodes of self-poisoning during the study period. There were marked differences in management between centres. There was a fivefold difference in the rate of admission to a medical bed (16.5%-81.3%), and a twofold difference in the rate of psychosocial assessment (28.5%-57.7%). These differences remained after adjustment for demographic and clinical factors. Hospital costs per episode varied from pound 228 to pound 422 and repetition rate ranged from 10% to 16%. Psychosocial assessment was associated with a twofold reduction in the risk of repetition.

CONCLUSIONS

The marked variability of services for self-poisoning continue. It seems likely that this is having a detrimental effect on patient outcomes. Large scale intervention studies are required to inform both clinical practice and service provision.

Thoracolumbar disc disease in large dogs: a study of 99 cases

The records of 99 dogs weighing over 20 kg with thoracolumbar disc disease were reviewed. Two types of disc disease were recognised: degenerative nuclear extrusion (n=63) and degenerative annular protrusion (n=36). Sixty-nine per cent of the affected discs were located between T12-T13 and L2-L3. Of the 63 dogs with degenerative nuclear extrusions, 35 were non-ambulatory and seven had no conscious pain perception at the time of presentation. Decompressive surgery was performed in 55 dogs, four dogs were managed non-surgically and three dogs were euthanased. A successful outcome was achieved in 49 (78 per cent) cases as assessed by the authors and in 53 (84 per cent) cases as assessed by the owners. Mean follow-up time was 11.7 months (range 1.5 to 48 months). Five dogs subsequently lost the ability to ambulate on their hindlimbs. Myelographic investigations in three of these dogs revealed a second thoracolumbar degenerative nuclear extrusion. Of the 36 dogs with degenerative annular protrusions, seven were non-ambulatory at the time of presentation. Fifteen cases had multiple protrusions. Twenty dogs were managed non-surgically, 12 surgically and four were euthanased. A successful outcome was achieved in eight (22 per cent) cases as assessed by the authors and in 19 (52 per cent) cases as assessed by the owners. Mean follow-up time was 9.2 months (range 1.5 to 30 months). The outcome of dogs with annular protrusions was significantly worse compared to the outcome of dogs with nuclear extrusions (P<0.001).

Caudal proximal tibial deformity and cranial cruciate ligament rupture in small-breed dogs

Eight dogs presented with chronic hindlimb lameness associated with cranial cruciate ligament rupture. Seven were small terriers. A caudal deformity of the proximal tibial shaft, originating at the proximal tibial physis, and an excessive caudal slope of the tibial plateau were present bilaterally in all dogs. The deformity was thought to be responsible for the cranial cruciate ligament failure and poor response to conservative management. Tibial plateau angles were in excess of 26 degrees in all dogs. The lameness was bilateral in three dogs. There was complete cranial cruciate ligament rupture in seven stifles and partial rupture in four. There were no meniscal injuries. Surgical correction resulted in a significant improvement (P<0.0001) in all dogs, with a mean follow-up of 12 months (range three to 24 months). There were no complications.