Clinical School (Austin Health) - Research Publications

Permanent URI for this collection

Search Results

Now showing 1 - 10 of 13
  • Item
    No Preview Available
    Advances in ureteroscopy
    Wetherell, DR ; Ling, D ; Ow, D ; Koonjbeharry, B ; Sliwinski, A ; Weerakoon, M ; Papa, N ; Lawrentschuk, N ; Bolton, DM (AME PUBL CO, 2014-09)
    Ureteroscopy (URS) is a procedure which has been constantly evolving since the development of first generation devices 40 years ago. Progress towards smaller and more sophisticated equipment has been particularly rapid in the last decade. We review the significant steps that have been made toward improving outcomes and limiting morbidity with this procedure which is central to the management of urolithiasis and other upper urinary tract pathology.
  • Item
    No Preview Available
    A multilingual evaluation of current health information on the Internet for the treatments of benign prostatic hyperplasia
    Chen, EC ; Manecksha, RP ; Abouassaly, R ; Bolton, DM ; Reich, O ; Lawrentschuk, N (ELSEVIER INC, 2014-12)
    PURPOSE: To compare the quality of current Internet information on benign prostatic hyperplasia (BPH) and its surgical and medical managements across four Western languages and a comparative analysis of website sponsors. BPH Internet information quality is particularly relevant in an era of expanding, minimally invasive and surgical therapies. However, no comprehensive analysis exists. METHODS: World Health Organization Health on the Net (HON) principles may be applied to websites using an automated toolbar function. Using a search engine (www.google.com), 9,000 websites were assessed using keywords related to BPH and its medical and surgical treatment in English, French, German, and Spanish. The first 150 websites in each language had HON principles measured whilst a further analysis of site sponsorship was undertaken. RESULTS: Very few BPH websites had greater than ten per cent HON accredited with significant differences (P<0.001) based on terms used for BPH, its medical and surgical management. Tertiles (thirds) of the first 150 websites returned differences in accredited websites (P<0.0001). English language had most accredited websites. Odds ratios for different terms returning accredited websites also were significantly different across terms (P<0.001). Websites were largely commercially sponsored. CONCLUSIONS: A lack of validation of most BPH sites should be appreciated with discrepancies in quality and number of websites across diseases, languages and also between medical and alternate terms. Physicians should participate in and encourage the development of informative, ethical and reliable health websites on the Internet and direct patients to them.
  • Item
    Thumbnail Image
    An Investigation of the Basic Physics of Irrigation in Urology and the Role of Automated Pump Irrigation in Cystoscopy
    Chang, D ; Manecksha, RP ; Syrrakos, K ; Lawrentschuk, N (HINDAWI PUBLISHING CORPORATION, 2012)
    OBJECTIVE: To investigate the effects of height, external pressure, and bladder fullness on the flow rate in continuous, non-continuous cystoscopy and the automated irrigation fluid pumping system (AIFPS). MATERIALS: Each experiment had two 2-litre 0.9% saline bags connected to a continuous, non-continuous cystoscope or AIFPS via irrigation tubing. Other equipment included height-adjustable drip poles, uroflowmetry devices, and model bladders. METHODS: In Experiment 1, saline bags were elevated to measure the increment in flow rate. In Experiment 2, saline bags were placed under external pressures to evaluate the effect on flow rate. In Experiment 3, flow rate changes in response to variable bladder fullness were measured. RESULTS: Elevating saline bags caused an increase in flow rates, however the increment slowed down beyond a height of 80 cm. Increase in external pressure on saline bags elevated flow rates, but inconsistently. A fuller bladder led to a decrease in flow rates. In all experiments, the AIFPS posted consistent flow rates. CONCLUSIONS: Traditional irrigation systems were susceptible to changes in height of irrigation solution, external pressure application, and bladder fullness thus creating inconsistent flow rates. The AIFPS produced consistent flow rates and was not affected by any of the factors investigated in the study.
  • Item
    Thumbnail Image
    The impact of fluid intervention on complications and length of hospital stay after pancreaticoduodenectomy (Whipple's procedure)
    Weinberg, L ; Wong, D ; Karalapillai, D ; Pearce, B ; Tan, CO ; Tay, S ; Christophi, C ; McNicol, L ; Nikfarjam, M (BIOMED CENTRAL LTD, 2014-05-14)
    BACKGROUND: There is limited information on the impact on perioperative fluid intervention on complications and length of hospital stay following pancreaticoduodenectomy. Therefore, we conducted a detailed analysis of fluid intervention in patients undergoing pancreaticoduodenectomy at a university teaching hospital to test the hypothesis that a restrictive intravenous fluid regime and/or a neutral or negative cumulative fluid balance, would impact on perioperative complications and length of hospital stay. METHODS: We retrospectively obtained demographic, operative details, detailed fluid prescription, complications and outcomes data for 150 consecutive patients undergoing pancreaticoduodenectomy in a university teaching hospital. Prognostic predictors for length of hospital stay and complications were determined. RESULTS: One hundred and fifty consecutive patients undergoing pancreaticoduodenectomy were evaluated between 2006 and 2012. The majority of patients were, middle-aged, overweight and ASA class III. Postoperative complications were frequent and occurred in 86 patients (57%). The majority of complications were graded as Clavien-Dindo Class 2 and 3. Postoperative pancreatic fistula occurred in 13 patients (9%), and delayed gastric emptying occurred in 25 patients (17%). Other postoperative surgical complications included sepsis (22%), bile leak (4%), and postoperative bleeding (2%). Serious medical complications included pulmonary edema (6%), myocardial infarction (8%), cardiac arrhythmias (13%), respiratory failure (8%), and renal failure (7%). Patients with complications received a higher median volume of intravenous therapy and had higher cumulative positive fluid balances. Postoperative length of stay was significantly longer in patients with complications (median 25 days vs. 10 days; p < 0.001). After adjustment for covariates, a fluid balance of less than 1 litre on postoperative day 1 and surgeon caseloads were associated with the development of complications. CONCLUSIONS: In the context of pancreaticoduodenectomy, restrictive perioperative fluid intervention and negative cumulative fluid balance were associated with fewer complications and shorter length of hospital stay. These findings provide good opportunities to evaluate strategies aimed at improving perioperative care.
  • Item
    Thumbnail Image
    Current role of salvage robotic-assisted laparoscopic prostatectomy
    Wetherell, D ; Bolton, D ; Kavanagh, L ; Perera, M (SPRINGER, 2013-06)
    OBJECTIVES: Salvage Robotic-Assisted Laparoscopic Prostatectomy (sRALP) is a treatment option for biochemical recurrence (BCR) in prostate cancer. It is a new and presently uncommonly performed procedure, which may be technically challenging. We aim to summarise the current literature regarding sRALP with specific reference to patient selection, complications and peri-operative functional and oncological outcomes. METHODS: A comprehensive and critical review of all peer-reviewed publications regarding sRALP. RESULTS: Within the body of literature, we identified six low-volume case-series studies analysing outcomes of sRALP. Overall, peri-operative outcomes were encouraging with low complication rates and estimated blood loss (EBL) equivocal to open and laparoscopic salvage radical prostatectomy (sRP). Long-term follow-up for functional and oncological outcomes was limited. From the limited follow-up data, the current sRALP studies show similar BCR compared to large-volume open sRP series. Potency outcomes were poor post-sRALP. CONCLUSIONS: Salvage Robotic-Assisted Laparoscopic Prostatectomy is a technically feasible operation with a low risk of significant associated complications. Robotic technology can aid the surgeon in salvage prostatectomy. Data on functional and oncological outcomes lack long-term information but initial results are encouraging. Larger series with longer follow-up periods are necessary to draw significant conclusions about the efficacy of sRALP.
  • Item
    Thumbnail Image
    Testosterone levels increase in association with recovery from acute fracture in men
    Cheung, AS ; Baqar, S ; Sia, R ; Hoermann, R ; Iuliano-Burns, S ; Vu, TDT ; Chiang, C ; Hamilton, EJ ; Gianatti, E ; Seeman, E ; Zajac, JD ; Grossmann, M (SPRINGER LONDON LTD, 2014-08)
    UNLABELLED: In this longitudinal case-control study, acute fracture was associated with low serum testosterone, which was transient in 43% of men. While assessment of gonadal status is part of the assessment of bone fragility, measurement of testosterone in the early period after fracture may overestimate the prevalence of androgen deficiency. INTRODUCTION: Measurement of circulating testosterone is recommended in the evaluation of bone fragility in men. Since acute illness can transiently decrease circulating testosterone, we quantified the association of acute fracture and serum testosterone levels. METHODS: A case-control study was conducted involving 240 men with a radiologically confirmed minimal trauma fracture presenting to a tertiary referral hospital and 89 age-matched men without a history of minimal trauma fracture serving as controls. Follow-up testosterone levels 6 months after baseline were available for 98 cases and 27 controls. Results were expressed as the median and interquartile (IQR) range. RESULTS: Compared to controls, cases had lower total testosterone [TT, 7.2 (3.5, 10.8) vs 13.6 (10.9, 17.1) nmol/L, p < 0.001]. The 143 cases treated as inpatients had lower testosterone levels than the 97 cases treated as outpatients [TT 4.7 (2.3, 8.1) vs 10.3 (7.5, 12.7) nmol/L, p < 0.001]. Group differences in calculated free testosterone (cFT) were comparable to the group differences in TT. At follow-up, in 98 cases, median TT increased from 6.5 nmol/L (3.2, 8.5) to 9.6 nmol/L (6.9, 12.0) p < 0.0001, and SHBG remained unchanged. Of cases with low testosterone, 43% with TT <10 nmol/L and/or cFT <230 pmol/L at presentation were reclassified as androgen sufficient at follow-up. TT was unchanged in the controls. CONCLUSIONS: Low testosterone levels in men presenting with an acute fracture may, at least in part, be due to an acute, fracture-associated, stress response. To avoid over diagnosis, evaluation for testosterone deficiency should be deferred until recovery from the acute event.
  • Item
    Thumbnail Image
    Hyperexpression of α-hemolysin explains enhanced virulence of sequence type 93 community-associated methicillin-resistant Staphylococcus aureus
    Chua, KYL ; Monk, IR ; Lin, Y-H ; Seemann, T ; Tuck, KL ; Porter, JL ; Stepnell, J ; Coombs, GW ; Davies, JK ; Stinear, TP ; Howden, BP (BMC, 2014-02-10)
    BACKGROUND: The community-associated methicillin-resistant S. aureus (CA-MRSA) ST93 clone is becoming dominant in Australia and is clinically highly virulent. In addition, sepsis and skin infection models demonstrate that ST93 CA-MRSA is the most virulent global clone of S. aureus tested to date. While the determinants of virulence have been studied in other clones of CA-MRSA, the basis for hypervirulence in ST93 CA-MRSA has not been defined. RESULTS: Here, using a geographically and temporally dispersed collection of ST93 isolates we demonstrate that the ST93 population hyperexpresses key CA-MRSA exotoxins, in particular α-hemolysin, in comparison to other global clones. Gene deletion and complementation studies, and virulence comparisons in a murine skin infection model, showed unequivocally that increased expression of α-hemolysin is the key staphylococcal virulence determinant for this clone. Genome sequencing and comparative genomics of strains with divergent exotoxin profiles demonstrated that, like other S. aureus clones, the quorum sensing agr system is the master regulator of toxin expression and virulence in ST93 CA-MRSA. However, we also identified a previously uncharacterized AraC/XylS family regulator (AryK) that potentiates toxin expression and virulence in S. aureus. CONCLUSIONS: These data demonstrate that hyperexpression of α-hemolysin mediates enhanced virulence in ST93 CA-MRSA, and additional control of exotoxin production, in particular α-hemolysin, mediated by regulatory systems other than agr have the potential to fine-tune virulence in CA-MRSA.
  • Item
    Thumbnail Image
    Renal Structure in Normoalbuminuric and Albuminuric Patients With Type 2 Diabetes and Impaired Renal Function
    Ekinci, EI ; Jerums, G ; Skene, A ; Crammer, P ; Power, D ; Cheong, KY ; Panagiotopoulos, S ; McNeil, K ; Baker, ST ; Fioretto, P ; MacIsaac, RJ (AMER DIABETES ASSOC, 2013-11)
    OBJECTIVE: The structural basis of normoalbuminuric renal insufficiency in patients with type 2 diabetes remains to be elucidated. We compared renal biopsy findings in patients with type 2 diabetes and estimated glomerular filtration rate (eGFR) and measured GFR of <60 mL/min/1.73 m2, associated with either normo-, micro-, or macroalbuminuria. RESEARCH DESIGN AND METHODS: In patients with normo- (n = 8) or microalbuminuria (n = 6), renal biopsies were performed according to a research protocol. In patients with macroalbuminuria (n = 17), biopsies were performed according to clinical indication. Findings were categorized according to the Fioretto classification: category 1 (C1), normal/near normal; category 2 (C2), typical diabetic nephropathy (DN) with predominantly glomerular changes; and category 3 (C3), atypical with disproportionately severe interstitial/tubular/vascular damage and with no/mild diabetic glomerular changes. RESULTS: In our study population (mean eGFR 35 mL/min/1.73 m2), typical glomerular changes (C2) of DN were observed in 22 of 23 subjects with micro- or macroalbuminuria compared with 3 of 8 subjects with normoalbuminuria (P = 0.002). By contrast, predominantly interstitial or vascular changes (C3) were seen in only 1 of 23 subjects with micro- or macroalbuminuria compared with 3 of 8 normoalbuminuric subjects (P = 0.08). Mesangial area increased progressively from normal controls to patients with type 2 diabetes and normo-, micro-, and macroalbuminuria. Varying degrees of arteriosclerosis, although not necessarily the predominant pattern, were seen in seven of eight subjects with normoalbuminuria. CONCLUSIONS: Typical renal structural changes of DN were observed in patients with type 2 diabetes and elevated albuminuria. By contrast, in normoalbuminuric renal insufficiency, these changes were seen less frequently, likely reflecting greater contributions from aging, hypertension, and arteriosclerosis.
  • Item
    Thumbnail Image
    Glucagon-like peptide 1 and peptide YY are in separate storage organelles in enteroendocrine cells
    Cho, H-J ; Robinson, ES ; Rivera, LR ; McMillan, PJ ; Testro, A ; Nikfarjam, M ; Bravo, DM ; Furness, JB (SPRINGER, 2014-07)
    A sub-group of enteroendocrine cells (L cells) release gastrointestinal hormones, GLP-1 and PYY, which have different but overlapping physiological effects, in response to intraluminal nutrients. Whilst their release profiles are not identical, how the plasma levels of these two hormones are differentially regulated is not well understood. We investigate the possibility that GLP-1 and PYY are in separate storage vesicles. In this study, the subcellular location of GLP-1 and PYY storage organelles is investigated using double-labelling immunohistochemistry, super resolution microscopy and high-resolution confocal microscopy. In all species tested, human, pig, rat and mouse, most cytoplasmic stores that exhibited GLP-1 or PYY immunofluorescence were distinct from each other. The volume occupancy, determined by 3D analysis, overlapped by only about 10∼20 %. At the lower resolution achieved by conventional confocal microscopy, there was also evidence of GLP-1 and PYY being in separate storage compartments but, in subcellular regions where there were many storage vesicles, separate storage could not be resolved. The results indicate that different storage vesicles in L cells contain predominantly GLP-1 or predominantly PYY. Whether GLP-1 and PYY storage vesicles are selectively mobilised and their products are selectively released needs to be determined.
  • Item
    Thumbnail Image
    Lactation is associated with greater maternal bone size and bone strength later in life
    Wiklund, PK ; Xu, L ; Wang, Q ; Mikkola, T ; Lyytikainen, A ; Voelgyi, E ; Munukka, E ; Cheng, SM ; Alen, M ; Keinanen-Kiukaanniemi, S ; Cheng, S (SPRINGER LONDON LTD, 2012-07)
    SUMMARY: The association between lactation and bone size and strength was studied in 145 women 16 to 20 years after their last parturition. Longer cumulative duration of lactation was associated with larger bone size and strength later in life. INTRODUCTION: Pregnancy and lactation have no permanent negative effect on maternal bone mineral density but may positively affect bone structure in the long term. We hypothesized that long lactation promotes periosteal bone apposition and hence increasing maternal bone strength. METHODS: Body composition, bone area, bone mineral content, and areal bone mineral density of whole body and left proximal femur were assessed using DXA, and cross-sectional area and volumetric bone mineral density of the left tibia shaft were measured by pQCT in 145 women (mean age 48 years, range 36-60 years) 16 to 20 years after their last parturition. Hip (HSI) and tibia strength indexes (TBSI) were calculated. Medical history and lifestyle factors including breastfeeding patterns and durations were collected via a self-administered questionnaire. Weight change during each pregnancy was collected from personal maternity tracking records. RESULTS: Sixteen to 20 years after the last parturition, women who had breastfed in total more than 33 months in their life, regardless of the number of children, had greater bone strength estimates of the hip (HSI = 1.92 vs. 1.61) and the tibia (TBSI = 5,507 vs. 4,705) owing to their greater bone size than mothers who had breastfed less than 12 months (p < 0.05 for all). The differences in bone strength estimates were independent of body height and weight, menopause status, use of hormone replacement therapy, and present leisure time physical activity level. CONCLUSION: Breastfeeding is beneficial to maternal bone strength in the long run.