Mobile-bearing lateral unicompartmental knee replacement with the Oxford domed tibial component: an independent series

The Oxford mobile-bearing unicompartmental knee replacement (UKR) is an effective and safe treatment for osteoarthritis of the medial compartment. The results in the lateral compartment have been disappointing due to a high early rate of dislocation of the bearing. A series using a newly designed domed tibial component is reported. The first 50 consecutive domed lateral Oxford UKRs in 50 patients with a mean follow-up of three years (2.0 to 4.3) were included. Clinical scores were obtained prospectively and Kaplan-Meier survival analysis was performed for different endpoints. Radiological variables related to the position and alignment of the components were measured. One patient died and none was lost to follow-up. The cumulative incidence of dislocation was 6.2% (95% confidence interval (CI) 2.0 to 17.9) at three years. Survival using revision for any reason and aseptic revision was 94% (95% CI 82 to 98) and 96% (95% CI 85 to 99) at three years, respectively. Outcome scores, visual analogue scale for pain and maximum knee flexion showed a significant improvement (p < 0.001). The mean Oxford knee score was 43 (SD 5.3), the mean Objective American Knee Society score was 91 (SD 13.9) and the mean Functional American Knee Society score was 90 (SD 17.5). The mean maximum flexion was 127° (90° to 145°). Significant elevation of the lateral joint line as measured by the proximal tibial varus angle (p = 0.04) was evident in the dislocation group when compared with the non-dislocation group. Clinical results are excellent and short-term survival has improved when compared with earlier series. The risk of dislocation remains higher using a mobile-bearing UKR in the lateral compartment when compared with the medial compartment. Patients should be informed about this complication. To avoid dislocations, care must be taken not to elevate the lateral joint line.

Laparotomy for blunt abdominal trauma in a civilian trauma service

This report looks at the group of patients who required a laparotomy for blunt torso trauma at a busy metropolitan trauma service in South Africa. Methods. A prospective trauma registry is maintained by the surgical services of the Pietermaritzburg metropolitan complex. This registry is interrogated retrospectively. All patients who required admission for blunt torso trauma over the period September 2006 - September 2007 were included for review. Proformas documenting mechanism of injury, age, vital signs, blood gas, delay in presentation, length of hospital stay, intensive care unit stay and operative details were completed. Results. A total of 926 patients were treated for blunt trauma by the Pietermaritzburg metropolitan services during the period under consideration. A cohort of 65 (8%) required a laparotomy for blunt trauma during this period. There were 17 females in this group. The mechanisms of injury were motor vehicle accident (MVA) (27), pedestrian vehicle accident (PVA) (21), assault (5), fall from a height (3), bicycle accident (6), quad bike accident (1) and tractor-related accident (2). The following isolated injuries were discovered at laparotomy: liver (9), spleen (5), diaphragm (1), duodenum (2), small bowel (8), mesentery (8) bladder (10), gallbladder (1), stomach (2), colon/rectum (2) and retrohepatic vena cava (1). The following combined injuries were discovered: liver and diaphragm (2), spleen and pancreas (1), spleen and liver (2), spleen, aorta and diaphragm (1), spleen and bladder (1) and small bowel and bladder (2). Eighteen patients in the series (26%) required relaparotomy. In 10 patients temporary abdominal containment was needed. The mortality rate was 26% (18 patients). There were 6 deaths from massive bleeding, all within 6 hours of operation, and 3 deaths from renal failure; the remaining 9 patients died of multiple organ failure. There were 8 negative laparotomies (7%). In the negative laparotomy group false-positive computed tomography (CT) scan findings were a problem in 3 cases, in 1 case hypotension and a fractured pelvis on admission prompted laparotomy, and in the other cases clinical findings prompted laparotomy. All patients who underwent negative laparotomy survived. There were 10 pelvic fractures, 5 lower limb fractures, 2 spinal injuries, 4 femur fractures and 2 upper limb fractures. CT scans were done in 25 patients. In 20 patients the systolic blood pressure on presentation was <90 mmHg and in 41 the pulse rate was >110 beats/min. In 16 patients there was a base excess of <-4 on presentation. Conclusion. Laparotomy is needed in less than 10% of patients who sustain blunt abdominal trauma. Solid visceral injury requiring laparotomy presents with haemodynamic instability. Hollow visceral injury has a more insidious presentation and is associated with a delay in diagnosis. CT scan is the most widely used investigation in blunt abdominal trauma. It is both sensitive and specific for solid visceral injury, but its accuracy for the diagnosis of hollow visceral injury is less well defined. Clinical suspicion must be high, and hollow visceral injury needs to be actively excluded.

Identification of markers of prostate cancer progression using candidate gene expression

BACKGROUND

Metastatic prostate cancer (PCa) has no curative treatment options. Some forms of PCa are indolent and slow growing, while others metastasise quickly and may prove fatal within a very short time. The basis of this variable prognosis is poorly understood, despite considerable research. The aim of this study was to identify markers associated with the progression of PCa.

METHODS

Artificial neuronal network analysis combined with data from literature and previous work produced a panel of putative PCa progression markers, which were used in a transcriptomic analysis of 29 radical prostatectomy samples and correlated with clinical outcome.

RESULTS

Statistical analysis yielded seven putative markers of PCa progression, ANPEP, ABL1, PSCA, EFNA1, HSPB1, INMT and TRIP13. Two data transformation methods were utilised with only markers that were significant in both selected for further analysis. ANPEP and EFNA1 were significantly correlated with Gleason score. Models of progression co-utilising markers ANPEP and ABL1 or ANPEP and PSCA had the ability to correctly predict indolent or aggressive disease, based on Gleason score, in 89.7% and 86.2% of cases, respectively. Another model of TRIP13 expression in combination with preoperative PSA level and Gleason score was able to correctly predict recurrence in 85.7% of cases.

CONCLUSION

This proof of principle study demonstrates a novel association of carcinogenic and tumourigenic gene expression with PCa stage and prognosis.

DEHP and its active metabolites: leaching from different tubing types, impact on proinflammatory cytokines and adhesion molecule expression. Is there a subsumable context?

Introduction: Di(2-ethylhexyl)phthalate (DEHP) is suspected to be toxic for several reasons. During contact with a lipophilic medium, DEHP leaks from polyvinylchloride (PVC), but its influence on inflammatory reactions remains unknown. We examined specific DEHP leaching out of different tubing types, the possibly modulated liberation of proinflammatory cytokines and the induction of adhesion molecule expression in primary endothelial cells.

Materials and Methods: Blood samples were circulated in traditional PVC, nodioctyl phthalate (DOP) PVC and heparin-coated PVC tubing within a Chandler loop model. The blood was tested for the concentration of DEHP and its active metabolites as well as the liberation of the proinflammatory cytokines TNFα and IL1ß. Furthermore, we exposed human endothelial cells to circulated blood and analysed them for the expression of the adhesion molecules ICAM-1, VCAM-1 and E-selectin.

Results: In contrast to the other tubing, PVC tubing showed significantly elevated DEHP levels, but no alteration was observed concerning a potential up-regulation of the cytokines or activation of the endothelial adhesion molecule receptors.

Conclusions: Our data conclude that there is no correlation between DEHP leaching and the inflammatory response after ECC support, but this study showed that even DEHP-free material is leaching DEHP and its toxic metabolites.

Transfection of short-interfering RNA silences adhesion molecule expression on cardiac microvascular cells

BACKGROUND

Acute rejection reactions and the development of graft arterial disease are serious limitations after transplantation. Both are connected to the expression of adhesion molecules on the activated microvascular endothelium of the allograft.

METHODS

siRNA-mediated silencing of ESELE, ICAM-1, and VCAM-1 on human cardiac microvascular cells (HCMEC) was investigated in order to inhibit leukocyte-endothelial interactions. HCMEC were investigated for the time-dependent expression of ESELE, ICAM-1, and VCAM-1 after TNF-α stimulation and for siRNA mediated suppression using a nonviral transfecting approach. Furthermore, the effects of siRNA transfection on leukocyte binding to the endothelium were analyzed.

RESULTS

Transfection with siRNA induced a significant suppression of adhesion molecule expression, regardless of whether there had been a prior single or cocktail transfection of the sequences ( P < 0.05). The quantity of attaching leukocytes was significantly reduced after an equal silencing of adhesion molecules ( P < 0.05).

CONCLUSIONS

This investigation demonstrates that liposomal transfection of HCMEC with specific siRNA sequences is capable of both repressing adhesion molecule expression and of reducing subsequent leukocyte-endothelial actions.

Resveratrol suppresses apoptosis in intact human cardiac tissue - in vitro model simulating extracorporeal circulation

AIM

After cardioplegia and subsequent reperfusion of the myocardium as employed in cardiac surgery, ischemia/reperfusion injury of the myocardium can induce apoptosis. The aim of this study was to evaluate the anti-apoptotic properties of resveratrol, a phenolic phytoalexin present in grape skins and especially red wines during simulated cardioplegia (cp) and reperfusion (rep) in an in-vitro microperfusion model on human myocardium, which to our knowledge has not been investigated yet.

METHODS

Cardiac specimens were retrieved from the right auricle of patients undergoing elective coronary artery bypass graft before induction of cardiopulmonary bypass. Cardiac specimens, with resveratrol (10 µM) (N.=15) and w/o resveratrol (control, N.=15) were exposed in vitro to varying periods of cp/rep (30/10, 60/20, 120/40 min) in a microperfusion chamber. For detection of apoptosis anti-activated-caspase-3, PARP-1 cleavage immunostaining and real-time PCR for gene expression of cardiac cytokines like BNP, NF-κB1, NF-κB2, E-Selectin, Troponin and TNF-α were employed.

CONTROL GROUP

the longer the cp/rep period lasted the higher were the rate of anti-activated-caspase-3 positive cardiomyocytes (21.26±2.07% ‑ 46.56±3.2%) and of PARP1-cleavage positive cardiomyocytes (23.29±2.16% ‑ 36.86±2.11%). Resveratrol group: apoptosis was suppressed significantly (P<0.05). Anti-activated-caspase-3 positive cardiomyocytes (13.45±4.35% ‑ 15.3±2.97%) and PARP1-cleavage positive cardiomyocytes (9.87±2.04% ‑ 11.77±3.42%). Resveratrol significantly suppressed the expression of BNP, NF-κB2, E-Selectin, Troponin and TNF-α in vitro (P<0.05).

CONCLUSION

Resveratrol significantly suppresses apoptosis under our applied in vitro conditions. This finding warrants further studies aiming suppression of ischemia/reperfusion injury in clinical settings.

Veins are no arteries: even moderate arterial pressure induces significant adhesion molecule expression of vein grafts in an ex vivo circulation model

AIM

Coronary artery bypass grafting (CABG) is a standard procedure for treatment of coronary heart disease. Eighty percent of all CABGs are performed with venous grafts which then get exposed to an arterial pressure after surgery. This widely used procedure, however, is complicated by the development of alterations in the vein graft wall, leading to a decreased patency rate and graft failure. This study enlightens the influence of an even moderate arterial pressure on the gene expression of adhesion molecules in venous grafts which play a decisive role for the early induction of atherogenesis.

METHODS

Segments of porcine vena jugularis and arteria carotis were mounted in a simulated bypass circuit and subjected to pulsatile flow. Vessel segments were examined for adhesion molecule expression with quantitative real-time - polymerase chain reaction (qRT-PCR) and adherence of leukocytes was observed by confocal laser scanning microscopy and scanning electron microscopy.

RESULTS

Veins grafts subjected to an even moderate arterial pressure showed a 14-fold increase of ICAM-1 expression already after 4 hours. An arterial pressure of around 100/80 mmHg was enough to stimulate the adhesion molecule expression Furthermore it led to a 9-fold increase of leukocyte adhesion to the venous endothelium, but, in contrast this was not the case in arteries.

CONCLUSION

This study showed, that already 100 mmHg upregulates the expression of several adhesion molecules in pig veins followed by increased adhesion of leukocytes. Therefore, our data demonstrate the advantage of arteries for CABG, and that new therapeutic strategies are urgently necessary to protect vein grafts either physically or pharmacologically if arteries are not available for CABG.

Epidemiology of paediatric out-of-hospital cardiac arrest in Melbourne, Australia

BACKGROUND

Previous studies of paediatric cardiac arrest have reported a low survival rate but there is limited data from Australia. We sought to determine the characteristics and outcomes of paediatric out-of-hospital cardiac arrest in Melbourne, Australia.

METHODS

Between October 1999 and June 2007, all cases of out-of-hospital cardiac arrest attended by emergency medical services in Melbourne, Australia were entered into a database (the Victorian Ambulance Cardiac Arrest Registry). Data on patients aged less than 16 years in cardiac arrest on arrival of ambulance paramedics was analysed.

RESULTS

There were 209 children in cardiac arrest on arrival of paramedics during the study period. Of these, resuscitation was not attempted in 16 children due to signs of definite death. Of the 193 children who had attempted resuscitation, 143 (74%) had an initial cardiac rhythm of asystole, 36 (18%) were in pulseless electrical activity and 14 (7%) were in ventricular fibrillation. There were 49 patients (25%) with return of spontaneous circulation at arrival to hospital of whom 14 (7%) survived to hospital discharge. Of 138 patients without return of a circulation, 120 were transported to hospital with continuing resuscitation and one survived (0.9%). Survival was higher in patients with an initial cardiac rhythm of ventricular fibrillation (5/14; 35%) compared with other rhythms (10/179; 4%), OR 9.38, 95% CI 2.64-33.2.

CONCLUSIONS

Overall, 7.7% of paediatric patients with out-of-hospital cardiac arrest survive to leave hospital. Increased survival was seen if the initial cardiac rhythm was ventricular fibrillation. Survival was very rare (<1%) unless there was return of spontaneous circulation prior to hospital arrival.

Surgery of pulmonary aspergillomas in immunocompromised patients

Introduction: Pulmonary aspergillosis is a devastating complication in immunocompromised patients. Timing of surgery is controversial and depends on the patients' general condition.

Methods: From 2000 to 2007, 16 patients (mean age 47 years, range 20–64) underwent surgery for pulmonary aspergillosis. All patients were receiving immunosuppressive drugs due to chemotherapy of hematological malignancies, ten with additional bone marrow or stem cell transplantation. Perioperatively, aspergillosis was treated with antifungal agents. If granulocyte numbers in the peripheral blood was below 1.0x10⁹/l, granulocyte stimulating factor and granulocyte transfusions were administered perioperatively.

Results: Four patients underwent lobectomy and wedge resections of the same lung, one patient bilobectomy, two patients lobectomy, eight patients wedge resections of one lung, and one patient wedge resections of both lungs. All patients survived surgery without major complications. Five patients were bone marrow or stem cell transplanted 1, 2, 3, 7 and 10 months after surgery. Three of them died due to recurrence of the underlying malignancy. All other patients are alive and free of fungal disease.

Conclusions: Timing of surgery in the context of antifungal therapy and adequate numbers of granulocytes and platelets in the peripheral blood appear essential for successful surgical therapy and avoidance of major complications.

Operating boundaries of full-scale advanced water reuse treatment plants: many lessons learned from pilot plant experience

Three Advanced Water Treatment Plants (AWTP) have recently been built in South East Queensland as part of the Western Corridor Recycled Water Project (WCRWP) producing Purified Recycled Water from secondary treated waste water for the purpose of indirect potable reuse. At Luggage Point, a demonstration plant was primarily operated by the design team for design verification. The investigation program was then extended so that the operating team could investigate possible process optimisation, and operation flexibility. Extending the demonstration plant investigation program enabled monitoring of the long term performance of the microfiltration and reverse osmosis membranes, which did not appear to foul even after more than a year of operation. The investigation primarily identified several ways to optimise the process. It highlighted areas of risk for treated water quality, such as total nitrogen. Ample and rapid swings of salinity from 850 to 3,000 mg/l-TDS were predicted to affect the RO process day-to-day operation and monitoring. Most of the setpoints used for monitoring under HACCP were determined during the pilot plant trials.

The effect of prostanoid precursors and inhibitors on platelet angiotensin II binding

Pregnancy-induced hypertension is characterised by an imbalance of arachidonic acid metabolites: Prostacyclin (PGI2) is vasodilatory and a potent inhibitor of platelet reactivity. Thromboxane (TXA2) induces vasoconstriction and platelet aggregation. Previous intervention studies have been aimed at increasing vasodilatation and decreasing platelet aggregation using low dose aspirin or dietary manipulation of prostaglandins. The aim of this study was to investigate the value of combining low dose aspirin with dietary fatty acid supplementation and its effects on platelet angiotensin II binding in non-pregnant women. Sixty non-pregnant, healthy female volunteers were recruited and randomly allocated to one of six treatment regimens which included aspirin taken alone and in combination with fish oil or evening primrose oil. A control group took no treatment. Platelet AII binding was determined before and after treatment for 1 month. There was no change in platelet angiotensin II binding after 1 month in the control group or in those who received evening primrose oil or fish oil alone. A significant decrease in binding was found in those who took aspirin in combination with fish oil (P = 0.03). An increase in binding was seen in those who took aspirin only, although this was not statistically significant (P = 0.14). A decrease was found in those who took aspirin in combination with evening primrose oil but again this was not statistically significant (P = 0.07). This study found that the combined effect of low-dose aspirin and fish oil causes a significant decrease in platelet angiotensin II binding not caused by either compound taken alone. Given that angiotensin II exerts its effect in part by direct interaction with vascular AII receptors, (platelets being used as 'models' of vascular myocytes), and that pre-eclampsia is associated with major pathophysiological changes in prostanoid metabolism, these pilot data provide a basis for further investigation.

Advanced oxidation for indirect potable reuse: a practical application in Australia

December 2008 marked the completion of Stage 2B of the Western Corridor Recycled Water (WCRW) Project in South East Queensland, Australia. With a maximum combined production capacity of 232 million litres of purified recycled water a day, it is the third largest recycled water scheme in the world and the largest in southern hemisphere. A seven-barrier approach has been used to ensure very highest quality, safe water is produced at all times for the purpose of indirect potable reuse. Three of these barriers occur in the advanced water treatment section of the WCRW Project: micro- or ultra-filtration (MF), reverse osmosis (RO), and H(2)O(2)/UV advanced oxidation. In addition to providing very efficient disinfection, the advanced oxidation process specifically aims at destroying compounds not fully rejected by RO that are potential health hazards. This includes N-nitrosodimethylamine (NDMA), which is a potential carcinogenic product likely to be formed by chlorination or chloramination of wastewaters. As in many other countries, Australia has adopted a stringent guideline limit for this compound of 10 ng/L in purified recycled water. After 16 months of operations of the WCRW Project's first plant, the advanced oxidation system has been proven effective in removing NDMA and ensuring 100% compliance with the regulation at a controlled cost.