Surgery (St Vincent's) - Research Publications

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    The relevance of ligament balancing in total knee arthroplasty: how important is it? A systematic review of the literature
    Babazadeh, S ; Stoney, JD ; Lim, K ; Choong, PFM (PAGEPRESS PUBL, 2009)
    Ligament balancing affects many of the postoperative criteria for a successful knee replacement. A balanced knee contributes to improved alignment and stability. Ligament balancing helps reduce wear and loosening of the joint. A patient with a balanced knee is more likely to have increased range of motion and proprioception, and decreased pain. All these factors help minimize the need for revision surgery. Complications associated with ligament balancing can include instability caused by over-balancing and the possibility of neurovascular damage during or as a result of ligament balancing. This article attempts to summarize the literature, to define a balanced knee, and outline the benefits and possible complications of ligament balancing. Different techniques, sequences, and tools used in ligament balancing, and their relevance in correcting various deformities are reviewed.
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    Robotic urology in the United Kingdom: experience and overview of robotic-assisted cystectomy
    Elhage, O ; Murphy, D ; Challacombe, B ; Rimington, P ; Khan, MS ; Dasgupta, P (SPRINGER LONDON LTD, 2008-02)
    In this article we look at the evolution of robotic technology in operative urology and the significant early contribution of Mr John Wickham. We explore the ergonomics of robotic technology and discuss financial issues from a British perspective. We share our clinical experience, describe the authors' robotic-assisted cystectomy technique, and conclude by exploring the patients' perception of this new treatment modality.
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    Differential upregulation of Nox homologues of NADPH oxidase by tumor necrosis factor-α in human aortic smooth muscle and embryonic kidney cells
    Moe, KT ; Aulia, S ; Jiang, F ; Chua, YL ; Koh, TH ; Wong, MC ; Dusting, GJ (WILEY, 2006)
    NADPH oxidases are important sources of vascular superoxide, which has been linked to the pathogenesis of atherosclerosis. Previously we demonstrated that the Nox4 subunit of NADPH oxidase is a critical catalytic component for superoxide production in quiescent vascular smooth muscle cells. In this study we sought to determine the role of Nox4 in superoxide production in human aortic smooth muscle cells (AoSMC) and embryonic kidney (HEK293) cells under proinflammatory conditions. Incubation with tumor necrosis factor-alpha (TNF-alpha, 10 ng/ml) for 12 h increased superoxide production in both cell types, whereas angiotensin II, platelet-derived growth factor or interleukin-1beta had little effects. Superoxide production was completely abolished by the NADPH oxidase inhibitors diphenyline iodonium and apocynin, but not by inhibitors of xanthine oxidase, nitric oxide synthase or mitochondrial electron transport. TNF-alpha upregulated the expression of Nox4 in AoSMC at both message and protein levels, while Nox1 and Nox2 were unchanged. In contrast, upregulation of Nox2 appeared to mediate the enhanced superoxide production by TNF-alpha in HEK293 cells. We suggest that Nox4 may be involved in increased superoxide generation in vascular smooth muscle cells under proinflammatory conditions.
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    The impact of 18-fluorodeoxyglucose positron emission tomography on the staging, management and outcome of anal cancer
    de Winton, E ; Heriot, AG ; Ng, M ; Hicks, RJ ; Hogg, A ; Milner, A ; Leong, T ; Fay, M ; MacKay, J ; Drummond, E ; Ngan, SY (NATURE PUBLISHING GROUP, 2009-03-03)
    Accurate inguinal and pelvic nodal staging in anal cancer is important for the prognosis and planning of radiation fields. There is evidence for the role of 18-fluorodeoxyglucose positron emission tomography (FDG-PET) in the staging and management of cancer, with early reports of an increasing role in outcome prognostication in a number of tumours. We aimed to determine the effect of FDG-PET on the nodal staging, radiotherapy planning and prognostication of patients with primary anal cancer. Sixty-one consecutive patients with anal cancer who were referred to a tertiary centre between August 1997 and November 2005 were staged with conventional imaging (CIm) (including computed tomography (CT), magnetic resonance imaging, endoscopic ultrasound and chest X-ray) and by FDG-PET. The stage determined by CIm and the proposed management plan were prospectively recorded and changes in stage and management as a result of FDG-PET assessed. Patients were treated with a uniform radiotherapy technique and dose. The accuracy of changes and prognostication of FDG-PET were validated by subsequent clinical follow-up. Kaplan-Meier survival analysis was used to estimate survival for the whole cohort and by FDG-PET and CIm stage. The tumour-stage group was changed in 23% (14 out of 61) as a result of FDG-PET (15% up-staged, 8% down-staged). Fourteen percent of T1 patients (3 out of 22), 42% of T2 patients (10 out of 24) and 40% of T3-4 patients (6 out of 15) assessed using CIm, had a change in their nodal or metastatic stage following FDG-PET. Sensitivity for nodal regional disease by FDG-PET and CIm was 89% and 62%, respectively. The staging FDG-PET scan altered management intent in 3% (2 out of 61) and radiotherapy fields in 13% (8 out of 61). The estimated 5-year overall survival (OS) and progression-free survival (PFS) for the cohort were 77.3% (95% confidence interval (CI): 55.3-90.4%) and 72.2% (95% CI: 51.5-86.4%), respectively. The estimated 5-year PFS for FDG-PET and CIm staged N2-3 disease was 70% (95% CI: 42.8-87.9%) and 55.3% (95% CI: 23.3-83.4%), respectively. FDG-PET shows increased sensitivity over CIm for staging nodal disease in anal cancer and changes treatment intent or radiotherapy prescription in a significant proportion of patients.
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    Neovascularization in an arterio-venous loop-containing tissue engineering chamber: role of NADPH oxidase
    Jiang, F ; Zhang, G ; Hashimoto, I ; Kumar, BS ; Bortolotto, S ; Morrison, WA ; Dusting, GJ (WILEY, 2008-10)
    Using an in vivo arterio-venous loop-containing tissue-engineering chamber, we have created a variety of vascularized tissue blocks, including functional myocardium. The viability of the transplanted cells is limited by the rate of neovascularization in the chamber. A Nox2-containing nicotinamide adenine dinucleotide phosphate (NADPH) oxidase is thought to have a critical role in ischaemic angiogenesis. In this study we investigated whether NADPH oxidase is involved in the neovascularization process in the tissue-engineering chamber. New blood vessels originating from the venous and the arterial ends of the loop could be identified after 3 days, and the vessel density (by lectin staining) peaked after 7 days and was maintained for at least 14 days. This was accompanied by granulation tissue formation and concomitant increase in the mRNA level of Nox4 NADPH oxidase. Although the total level of Nox2 mRNA in the chamber tissue decreased from day 3 to day 7, immunohistochemistry identified a strong expression of Nox2 in the endothelial cells of the new vessels. In human microvascular endothelial cells, the NADPH oxidase inhibitor apocynin reduced NADPH oxidase activity and inhibited the angiogenic responses in vitro. Local treatment with the NADPH oxidase inhibitors apocynin or gp91ds-tat peptide significantly suppressed the vessel growth in the chamber. In conclusion, NADPH oxidase-dependent redox signalling is important for neovascularization in this novel tissue-engineering chamber in vivo, and boosting this signalling might be a new approach to extending vascularization and tissue growth.
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    The correlation between colorectal cancer rates of proliferation and apoptosis and systemic cytokine levels; plus their influence upon survival
    Evans, C ; Morrison, I ; Heriot, AG ; Bartlett, JB ; Finlayson, C ; Dalgleish, AG ; Kumar, D (NATURE PUBLISHING GROUP, 2006-05-22)
    Colorectal cancer development is associated with a shift in host immunity with suppression of the cell-mediated immune system (CMI) and a predominance of humoral immunity (HI). Tumour progression is also associated with increased rates of cell proliferation and apoptosis. The aim of this study was to investigate whether these factors correlate and have an influence upon prognosis. Long-term follow-up was performed on 40 patients with colorectal cancer who had levels of tumour necrosis factor (TNF)-alpha, interferon (IFN)-gamma and interleukin (IL)-10 measured from stimulated blood cultures before surgery. Their archived tumour specimens were analysed to determine a Ki-67-derived proliferation index (PI) and a M30-derived apoptosis index (AI). Tumour necrosis factor-alpha levels negatively correlated to tumour proliferation (rho=-0.697, P=0.01). Interleukin-10 levels had a positive correlation with tumour proliferation (rho=0.452, P=0.05) and apoptosis (rho=0.587, P=0.01). Patient survival correlates to tumour pathological stage (P=0.0038) and vascular invasion (P=0.0014). An AI< or =0.6% and TNF-alpha levels > or =8148 pg ml(-1) correlate to improved survival (P=0.032, P=0.021). Tumour proliferation and apoptosis correlate to progressive suppression of the CMI-associated cytokine TNF-alpha and to and higher levels of IL-10. Survival is dependent upon the histological stage of the tumour, vascular invasion, rates of apoptosis and proliferation and systemic immunity which are all interconnected.
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    Clinical applications of molecular imaging in sarcoma evaluation.
    Hicks, RJ ; Toner, GC ; Choong, PFM (E-MED LTD, 2005-06-21)
    A wide range of molecular imaging techniques are available that can provide complementary information to conventional, anatomical imaging for the evaluation of known or suspected bone and soft tissue sarcomas. In particular, positron emission tomography (PET), particularly in the form of hybrid PET/CT technology, offers many potential advantages over current imaging approaches by delineating not only the extent of disease but also the biological heterogeneity that can exist both between and within sarcomas. This review discusses the clinical situations where nuclear medicine techniques can aid in the management of patients with sarcoma. These include biopsy guidance, whole body staging, therapeutic response assessment and evaluation of residual mass lesions after treatment.
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    Robotic-assisted surgery for benign urological conditions
    Murphy, DG ; Challacombe, BJ ; Zaheer, L-U-M ; Khan, MS ; Dasgupta, P (HINDAWI LTD, 2006)
    Robotic technology for use in surgery has advanced considerably in the past 10 years. This has become particularly apparent in urology where robotic-assisted radical prostatectomy using the da Vinci surgical system (Intuitive Surgical, CA) has become very popular. The use of robotic assistance for benign urological procedures is less well documented. This article considers the current robotic technology and reviews the situation with regard to robotic surgery for benign urological conditions.
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    Outcome of patients with osteosarcoma over 40 years of age: is angiogenesis a marker of survival?
    Ek, ETH ; Ojaimi, J ; Kitagawa, Y ; Choong, PFM (Springer Science and Business Media LLC, 2006-03-21)
    BACKGROUND: Osteosarcoma predominantly afflicts young people in their second and third decades of life. When osteosarcoma arises in patients older than 40 years, the prognosis is usually poorer compared to their younger counterparts. Although the clinical, histopathologic features and prognostic indicators are well defined for young patients, much less is known about affected adults. The purpose of this study is to describe our institution's experience with the management of osteosarcoma in patients greater than 40 years and also evaluate, by immunohistochemical analysis, the prognostic significance of microvessel density, as a marker of intratumoural angiogenesis. METHODS: A retrospective clinicopathological analysis was performed on 11 patients over the age of 40 years that were treated at our institution between 1996 and 2004. Archival pre-treatment biopsy tissue was retrieved for immunohistochemical staining against two endothelial cell markers (CD31 and CD34) and also against VEGF. Angiogenesis was assessed by determining the intratumoural microvessel density (MVD) and the degree of VEGF expression in these specimens. This was correlated with patient outcome in terms of local recurrence, metastasis and death. Histological results were also compared to a group of patients less than 40 years of age. RESULTS: Of the 11 patients, 9 were male and 2 were female and the mean age was 58 years (range, 42-85). In 7 patients, osteosarcoma arose secondarily from Paget's disease of the bone. The most common site involved was the humerus (7) followed by the femur (2) then pelvis (1) and ulna (1). At the time of diagnosis, 4 patients had metastatic disease. Preoperative chemotherapy was given to 4 patients, with a good response in 3 patients. Six patients underwent limb-sparing surgery, 4 had amputations and 1 was treated with radiotherapy alone. The mean follow up time was 31.5 months (range, 8-81). At this time, 4 patients (36%) had developed lung metastases and 5 patients (46%) had died. Overall survival was 54.5%. Intratumoural MVD was higher in patients over 40 years, although not statistically significant (p = 0.111, CD31; p = 0.134, CD34). VEGF was uniformly expressed in all sections, however no relationship was found between the degree of expression and patient age. CONCLUSION: The prognosis for older patients with osteosarcoma is generally poor. Initial presentation is commonly associated with metastatic disease and neoadjuvant chemotherapy is often avoided because of its side effects. Increased intratumoural vascularity may contribute to the poorer prognosis in these patients, however further studies are needed.