SUMMARY Transverse midshaft fractures of femurs from freshly euthanatized dogs were stabilized by means of 6 methods: (1) 3.5-mm bone plate and screws, (2) single intramedullary pin, (3) double intramedullary pins retrograded proximally and driven distally to the level of the femoral trochlea, (4) double intramedullary pins retrograded distally and driven proximally into the trochanteric region, (5) double intramedullary pinning in Rush pin fashion, and (6) multiple intramedullary pinning that filled the medullary cavity at the fracture site. All bones were subjected to torsional stress. The measured strain was converted to forces of torque and correlated with bone diameter to normalize the data. The forces of torque from each fixation technique were compared with each other and with the mean torque force necessary to fracture intact femurs. Torsional shear applied to plated femurs resulted in failure at a mean level of 33.8% of the calculated theoretic moment. Torsional forces were concentrated at one end of the plate and catastrophically failed at that point, whereas the fracture site remained rigidly fixed. There was no significant difference in the initial moment of torsional failure between the single intramedullary pin technique (0,05 Nm) and the double-pinning techniques (0.03 Co 0.04 Nm). The multiple-pinning technique was 1.8 to 3 times as effective in resisting rotational forces, compared with the other pinning techniques, but not significantly so.
Histological classification of laryngeal epithelial lesions is highly subjective, and methods of cytological detection are not well developed. Improved determination of aberrant cell cycle entry may allow increased objectivity in histological assessment and enable the development of less invasive diagnostic cytology tests. Sections of normal larynx (n=10), laryngeal dysplasia (n=20) and laryngeal squamous cell carcinoma (SCC) (n=10) were classified according to the Ljubljana classification and stained for markers of cell cycle entry, minichromosome maintenance protein-2 (Mcm-2) and Ki67. Expression patterns were compared using double labelling confocal microscopy. There was a correlation between Mcm-2 and Ki67 labelling indices (ρ=0.93; 95% CI [0.84, 0.97]) and both markers showed increased expression from normal epithelium to SCC (Mcm-2, P=0.001; Ki67, P=0.0002). Importantly, there was minimal expression of Mcm-2 or Ki67 in the most superficial layers of normal larynx and abnormal or atypical hyperplasia, in contrast to carcinoma in situ and SCC. Clusters of Mcm-2/5-positive cells were present in cytological preparations from SCC, but not from those showing atypical hyperplasia or inflammation in non-neoplastic tissue. Minichromosome maintenance protein-2 staining may increase the objectivity and reliability of histological grading of laryngeal epithelial lesions. Laryngeal brushings, combined with immuno-enhanced liquid-based cytology, could be useful, as a less invasive approach, to the detection of laryngeal malignant and premalignant lesions.
Primary care studies often encounter recruitment difficulties, but there is little evidence to inform solutions. As part of a National Institute for Health Research School for Primary Care Research and UK Clinical Research Network programme, we elicited research staff perspectives on factors facilitating or obstructing recruitment.To identify factors that experienced research staff consider important in successful recruitment and retention and their confidence in achieving them.An iterative series of three workshops was held. The third used a modified nominal group technique to categorize whether factors related to the 'context' in which the research took place, the 'content' of the study or the recruitment 'process' and to prioritize them by their importance to success.Eighteen research staff participated in the prioritization workshop. They prioritized positive attitudes of primary care staff towards research and trust of researchers by potential participants as major contextual factors affecting recruitment. Studies needed to be considered safe and relevant by staff and fit with practice systems. They proposed that researchers strengthen relationships with staff and participants and minimize workload for primary care teams. Although confident in many recruitment processes, respondents remained uncertain how to achieve cultural change so that research became part of normal practice activity and how best to motivate patients to participate.Research workers taking part identified factors which might be important in recruitment, several of which they expressed little confidence in addressing. Understanding how to improve recruitment is crucial if current efforts to strengthen primary care research are to bear fruit.
To study biomechanical characteristics of the normal and surgically altered canine thoracolumbar vertebral column to determine the effects of surgery and trauma on lateral stability.The T13-L1 vertebral motion units of 48 mixed-breed dogs were dissected free of surrounding musculature and prepared for biomechanical testing by cross-pinning the vertebral bodies and mounting in polymethylmethacrylate.Normal and surgically altered spinal specimens were subjected to lateral bending. The mean slope of the bending moment versus angular displacement curve and the load to failure were compared between treatment groups and significance was determined by the method of least squares (P < 0.05). Specimens were surgically altered by facetectomy, lateral fenestration, diskectomy, and combinations of these procedures. Each specimen was subjected to lateral bending to failure at a rate of 2.5 cm/min in a swing arm bending jig designed to simulate 4-point bending and subject the specimen to pure bending.Only specimens undergoing diskectomy had a significant decrease in slope and load at failure. Unilateral and bilateral facetectomies and fenestration induced a nonsignificant decrease in stiffness, compared with control specimens.Fenestrations and facetectomies do not appear to increase the risk of injury to the canine thora-columbar spinal cord during lateral bending.Fenestrations and facetectomies, as used in routine laminectomies, may be performed without concern for significant destabilization of the spine in lateral bending; however, it is possible that thoracolumbar spinal fractures involving only the vertebral body may significantly destabilize the spine in all modes of bending.
[Extract] Cultural diversity therefore has become a key characteristic of both countries national identities. It should be noted that there are a number of long-term settled communities in both Australia and New Zealand. The Chinese, for example, have immigrated to both countries since the 1880s. Indian and Pacific communities have been arriving in New Zealand over a considerable period of time. For the purpose of this chapter, however, the focus is on those more recently arrived refugee and migrant communities that are at risk of acute and chronic health problems to a greater extent than the general population, that is, those who lie in poverty, have little education and/or exhibit other characteristics of vulnerable populations in general. The chapter illustrates strategies that community nurses can adopt and utilise when working with these often vulnerable groups.
We describe a 64-year-old man who presented with a 9-month history of a progressive neurologic disturbance affecting principally his short-term memory, eye movements, and sense of balance. Computed tomography and magnetic resonance imaging showed a 3-cm mass in the left cerebellar hemisphere. This was removed at craniotomy and proved histologically to be a diffuse non-Hodgkin's lymphoma. Further investigation showed no evidence of lymphoma elsewhere in the body. Immunohistochemical studies with an extensive panel of monoclonal antibodies showed the tumor cells to be T cells staining with the markers UCHL1, MT1, OKT3, and OKT11. Cells of the helper phenotype predominated. A small admixed reactive population of polyclonal B cells and macrophages was also present. The proliferation count as judged with the antibody Ki67 was about 15%. Primary cerebral lymphoma is in itself a rare entity with most cases being of B-cell origin. Primary cerebral T-cell lymphoma is extremely rare and the few previously reported cases are reviewed.