Anti-hypertensive prescription practices in private hospitals in Malaysia: a prospective, non-interventional, observational study.

INTRODUCTION: In managing hypertension, monotherapy and sometimes a combination of more than one agent are used to achieve blood pressure (BP) control. The objective of this prospective, observational, multi-centre study was to assess the level of BP control in patients receiving one or more anti-hypertensive drugs in private medical centres in Malaysia according to the treatment regimens (monotherapy, free drug combinations and single pill combinations). MATERIALS AND METHODS: Data were collected through medical records and interview sessions with patients on current pharmacotherapy for hypertension management at baseline and 2-3 months later. Results are expressed as mean ± SD for continuous data and as frequencies and percentages for categorical data. RESULTS: Among 182 recruited patients, 89 (49%) achieved BP control by the end of the study. Majority (62/89) patients were on single-pill (monotherapy or SPC) antihypertensives. Majority (63/89) required more than two antihypertensives to achieve BP control. CONCLUSION: Both SPC and free drug combination antihypertensives reduced BPs, but physicians preferred SPC to improve BP control and increase treatment compliance.

Ground effect on the aerodynamics of three-dimensional hovering wings.

This paper reports the results of combined experimental and numerical studies on the ground effect on a pair of three-dimensional (3D) hovering wings. Parameters investigated include hovering kinematics, wing shapes, and Reynolds numbers (Re). The results are consistent with the observation by another study (Gao and Lu, 2008 Phys. Fluids, 20 087101) which shows that the cycle-averaged aerodynamic forces generated by two-dimensional (2D) wings in close proximity to the ground can be broadly categorized into three regimes with respect to the ground clearance; force enhancement, force reduction, and force recovery. However, the ground effect on a 3D wing is not as significant as that on a 2D flapping wing reported in (Lu et al 2014 Exp. Fluids, 55 1787); this could be attributed to a weaker wake capture effect on 3D wings. Also, unlike a 2D wing, the leading edge vortex (LEV) remains attached on a 3D wing regardless of ground clearance. For all the wing kinematics considered, the three above-mentioned regimes are closely correlated to a non-monotonic trend in the strength of downwash due to the restriction of root and tip vortex formation, and a positional shift of wake vortices. The root vortices in interaction with the ground induce an up-wash in-between the two wings, causing a strong 'fountain effect' (Maeda and Liu, 2013 J. Biomech. Sci. Eng., 8 344) that may increase the body lift of insects. The present study further shows that changes in wing planform have insignificant influence on the overall trend of ground effect except for a parallel shift in force magnitude, which is caused mainly by the difference in aspect ratio and leading edge pivot point. On the two Reynolds numbers investigated, the results for the low Re case of 100 do not deviate significantly from those of a higher Re = 5000 except for the difference in force magnitudes, since low Reynolds number generates lower downwash, weaker LEV, and lower rotational circulation. Additionally, lower Re leads to a weaker fountain effect.

Aspect ratio effects on revolving wings with Rossby number consideration.

Numerical simulations have been conducted to investigate the effect of aspect ratio (AR) on the mean lift generation of a revolving flat rectangular wing. The purpose of the study is to address some discrepancies reported in the literature regarding the influence of AR on mean lift coefficient. Here, we consider a range of AR from 1 to 10 and Rossby number (Ro) from 0.58 to 7.57, and our results show that different degrees of coupling between AR and Ro yield different trends of a mean lift coefficient with respect to increasing AR. The choice of reference velocity for the normalisation of mean lift forces also has a significant effect on the perceived AR effect. By isolating the effect of Ro, we found that higher AR produces higher mean lift coefficient until it plateaus at a sufficiently high AR. This finding is consistent with conventional fixed wing aerodynamics. Additionally, our results show that increasing AR reduces the three-dimensional wing tip effect and is beneficial to mean lift generation while higher Ro increases leading-edge vortex instability, which is detrimental to mean lift generation. Therefore, mean lift generation on revolving wings is dictated by the competition between these two factors, which represent two fundamentally independent phenomena.

A quasi-steady aerodynamic model for flapping flight with improved adaptability.

An improved quasi-steady aerodynamic model for flapping wings in hover has been developed. The purpose of this model is to yield rapid predictions of lift generation and efficiency during the design phase of flapping wing micro air vehicles. While most existing models are tailored for a specific flow condition, the present model is applicable over a wider range of Reynolds number and Rossby number. The effects of wing aspect ratio and taper ratio are also considered. The model was validated by comparing against numerical simulations and experimental measurements. Wings with different geometries undergoing distinct kinematics at varying flow conditions were tested during validation. Generally, model predictions of mean force coefficients were within 10% of numerical simulation results, while the deviations in power coefficients could be up to 15%. The deviation is partly due to the model not taking into consideration the initial shedding of the leading-edge vortex and wing-wake interaction which are difficult to account under quasi-steady assumption. The accuracy of this model is comparable to other models in literature, which had to be specifically designed or tuned to a narrow range of operation. In contrast, the present model has the advantage of being applicable over a wider range of flow conditions without prior tuning or calibration, which makes it a useful tool for preliminary performance evaluations.

Surveillance of enteric viruses and coliphages in a tropical urban catchment.

An assessment of the occurrence and concentration of enteric viruses and coliphages was carried out in highly urbanized catchment waters in the tropical city-state of Singapore. Target enteric viruses in this study were noroviruses, adenoviruses, astroviruses and rotaviruses. In total, 65 water samples were collected from canals and the reservoir of the Marina catchment on a monthly basis over a period of a year. Quantitative PCR (qPCR) and single agar layer plaque assay (SAL) were used to enumerate target enteric viruses and coliphages in water samples, respectively. The most prevalent pathogen were noroviruses, detected in 37 samples (57%), particularly norovirus genogroup II (48%), with a mean concentration of 3.7 × 10(2) gene copies per liter. Rotavirus was the second most prevalent virus (40%) with a mean concentration of 2.5 × 10(2) GC/L. The mean concentrations of somatic and male-specific coliphages were 2.2 × 10(2) and 1.1 × 10(2) PFU/100 ml, respectively. The occurrence and concentration of each target virus and the ratio of somatic to male-specific coliphages varied at different sampling sites in the catchment. For sampling sites with higher frequency of occurrence and concentration of viruses, the ratio of somatic to male-specific coliphages was generally much lower than other sampling sites with lower incidences of enteric viruses. Overall, higher statistical correlation was observed between target enteric viruses than between enteric viruses and coliphages. However, male-specific coliphages were positively correlated with norovirus concentrations. A multi-level integrated surveillance system, which comprises the monitoring of bacterial indicators, coliphages and selected enteric viruses, could help to meet recreational and surface water quality criteria in a complex urbanized catchment.

Is 6 months of neuroleptic withdrawal sufficient to distinguish drug-induced parkinsonism from Parkinson's disease?

BACKGROUND: Drug-induced parkinsonism (DIP) is the second commonest cause of akinetic-rigid syndrome in the western world. Differentiating DIP from Parkinson's disease (PD) may be a challenge to clinicians. One of the factors distinguishing DIP from PD is that discontinuation of the neuroleptic agent in DIP should relieve the symptoms of parkinsonism. The majority of the literature uses the 6-month timeframe between the neuroleptic withdrawal and resolution of the symptoms of parkinsonism. METHODS: We report two cases of DIP wherein the symptoms of parkinsonism persisted more than 6-months from withdrawal of the dopamine receptor blocking agent (DRBA) and the results of their ioflupane iodine-123 (DaT) single-photon emission computed tomography (SPECT) scan. DaT scan is a newly approved radiopharmaceutical in the United States indicated for striatal dopamine transporter visualization to assist in the evaluation of adult patients with suspected parkinsonian syndromes. RESULTS: The first case is a patient who developed parkinsonism from risperidone, while the second case developed parkinsonism from metoclopramide. In both cases, parkinsonism persisted 6 months after discontinuation of the DRBA, therefore DaT scan was obtained, showing normal striatal dopamine transporter uptake. Nine months after the discontinuation of the DRBA, parkinsonism was significantly improved in both patients but not completely resolved. CONCLUSION: Our two cases illustrate the possibility of persistent parkinsonism beyond 6-9 months from the time of neuroleptic withdrawal without evidence of presynaptic dopaminergic neuronal loss that would be suggestive of conversion to PD. We recommend that the official recommendation of the minimum time of neuroleptic withdrawal be modified to at least 1 year before entertaining the diagnosis of PD conversion in patients with exposure to DRBAs.

Ventilation rates in large commercial layer hen houses with two-year continuous monitoring.

1. Ventilation controls the indoor environment and is critical for poultry production and welfare. Ventilation is also crucial for assessing aerial pollutant emissions from the poultry industry. Published ventilation data for commercial layer houses have been limited, and are mostly based on short-term studies, mainly because monitoring airflow from large numbers of fans is technically challenging. 2. A two-year continuous ventilation monitoring trial was conducted at two commercial manure belt houses (A and B), each with 250 000 layers and 88 130-cm exhaust fans. All the fans were individually monitored with fan rotational speed sensors or vibration sensors. Differential static pressures across the house walls were also measured. Three fan performance assessment methods were applied periodically to determine fan degradations. Fan models were developed to calculate house ventilations. 3. A total of 693 and 678 complete data days, each containing >16 h of valid ventilation data, were obtained in houses A and B, respectively. The two-year mean ventilation rates of houses A and B were 2·08 and 2·10 m(3) h(-1) hen(-1), corresponding to static pressures of -36·5 and -48·9 Pa, respectively. For monthly mean ventilation, the maximum rates were 4·87 and 5·01 m(3) h(-1) hen(-1) in July 2008, and the minimum were 0·59 and 0·81 m(3) h(-1) hen(-1) in February 2008, for houses A and B, respectively. 4. The two-year mean ventilation rates were similar to those from a survey in Germany and a 6-month study in Indiana, USA, but were much lower than the 8·4 and 6·2 m(3) h(-1) hen(-1) from a study in Italy. The minimum monthly mean ventilation rates were similar to the data obtained in winter in Canada, but were lower than the minimum ventilation suggested in the literature. The lower static pressure in house B required more ventilation energy input. The two houses, although identical, demonstrated differences in indoor environment controls that represented potential to increase ventilation energy efficiency, and reduce carbon footprints and operational costs.

Characteristics of ammonia and carbon dioxide releases from layer hen manure.

1. Ammonia (NH(3)) is an important gaseous pollutant generated from manure in commercial poultry farms and has been an environmental, ecological, and health concern. Poultry manure also releases carbon dioxide (CO(2)), which is a greenhouse gas and is often used as a tracer gas to calculate building ventilation. 2. A 38-d laboratory study was conducted to evaluate the characteristics of NH(3) and CO(2) releases from layer hen manure using 4 manure reactors (122 cm tall, 38 cm internal diameter), which were initially filled with 66 cm deep manure followed by weekly additions of 5 cm to simulate manure accumulation in commercial layer houses. 3. The average daily mean (ADM) NH(3) and CO(2) release fluxes for the 4 reactors during the entire study were 1615 +/- 211 microg/s.m(2) (ADM +/- 95% confidence interval) and 100 +/- 03 mg/s.m(2), respectively. The daily mean NH(3) and CO(2) releases in individual reactors varied from 352 to 6791 microg/s.m(2) and from 66 to 205 mg/s.m(2), respectively. 4. The ADM NH(3) release flux was within the range of those obtained in 4 high-rise layer houses by Liang et al. (2005, Transactions of the ASAE, 48). However, the CO(2) release flux in this study was about 10 to 13 times as high as the data reported by Liang et al. (2005). Fresh manure had greater NH(3) release potential than the manure in the reactors under continuous ventilation. Manure with higher contents of moisture, total nitrogen, and ammonium in the 4th weekly addition induced 11 times higher NH(3) and 75% higher CO(2) releases immediately after manure addition compared with pre-addition releases.

Removal of arsenate from aqueous solution by nanocrystalline Mg/Al layered double hydroxide: sorption characteristics, prospects, and challenges.

Removal of arsenate (As(V)) from aqueous solution using both nanocrystalline and coprecipitated Mg/Al layered double hydroxides (LDHs) was examined under different sorption/desorption conditions. The surface area, pore volume, and pore size of the nanocrystalline LDH were significantly higher than those of the coprecipitated LDH, thus resulting in a higher As(V) sorption maximum than the coprecipitated LDH. The calculated activation energy (E(a)) value was 24.7 kJ/mol, suggesting the occurrence of anion exchange process for As(V) removal by the nanocrystalline LDH. The predominance of anion exchange process was further supported by the investigation of ionic strength effect, and XRD and FTIR analyses. The effect of aqueous matrix on As(V) sorption by the nanocrystalline LDH was found to increase in the order of nitrate < silica < sulfate < carbonate < phosphate. Regeneration study showed that a secondary sorption mechanism might occur concurrently for the As(V) sorption by nanocrystalline LDH besides the predominant anion exchange process. Prospects and challenges for practical application of the nanocrystalline LDH were also discussed in the latter part of this study.

Controlled field studies on soil aquifer treatment in a constructed coastal sandfill.

A controlled artificial recharge experiment was conducted to investigate the effect of soil aquifer treatment during percolation of secondary and tertiary (ultrafiltered) treated wastewater through the shallow vadoze zone of a newly constructed coastal sandfill. The sandfill is a reclaimed land constructed from marine sand dredged from the seabed. To obtain 1-D flow, a stainless steel column was driven to a depth of 2.5 m, penetrating the phreatic surface. Wastewater was percolated through the column under fully-saturated and unsaturated conditions. Infiltration rates, dissolved organic carbon (DOC) and ultra-violet absorption (UVA) were monitored. The wastewaters were recharged at similar infiltration rates of approximately 5.5 m/day and 3.5 m/day under fully-saturated and unsaturated conditions, respectively. In both cases, clogging occurred 40 days after the start of recharge, under saturated conditions. For secondary treated wastewater, DOC concentration (mg/l) reduced by 28% and 13% under unsaturated and saturated conditions, respectively. The corresponding UVA reduction was 19.4% and 14.1%. Similar reductions in DOC were observed for the tertiary treated wastewater; however, the reduction in UVA was higher; 28% and 22% under unsaturated and saturated conditions, respectively. On an mass removal (mg/m(2) DOC) basis, DOC reduction appeared to be more significant under unsaturated conditions. This is attributed to the presence of interstitial oxygen.

Mechanistic and thermodynamic studies of oxyanion sorption by various synthetic Mg/Al layered double hydroxides.

In this study, Mg/Al layered double hydroxides (LDHs) were investigated for their potential in scavenging several harmful oxyanions from aqueous solution. LDHs could effectively remove oxyanions and the selectivity of LDHs was governed by both the valencies and the ionic radii of the oxyanions. LDHs prepared by the fast coprecipitation with hydrothermal treatment (FCHT) method and sol-gel with solvothermal treatment method (SGST) had higher oxyanion (i.e. arsenate) removal efficiency than those prepared by the conventional routes, owing to their lower carbonate content, higher surface area, larger pore volume, larger pore size, and nanocrystalline characteristic. The sorption of arsenate by FCHT-LDH was found primarily due to anion exchange mechanism and might involve a secondary sorption mechanism. The negative DeltaG degrees for arsenate sorption confirmed the spontaneity of the removal process. The positive values of DeltaH degrees and DeltaS degrees provided further evidence of the anion exchange process in the removal mechanism.

Flow modeling in a novel non-perfusion conical bioreactor.

We have developed a bioreactor vessel design which has the advantages of simplicity and ease of assembly and disassembly, and with the appropriately determined flow rate, even allows for a scaffold to be suspended freely regardless of its weight. This article reports our experimental and numerical investigations to evaluate the performance of a newly developed non-perfusion conical bioreactor by visualizing the flow through scaffolds with 45 degrees and 90 degrees fiber lay down patterns. The experiments were conducted at the Reynolds numbers (Re) 121, 170, and 218 based on the local velocity and width of scaffolds. The flow fields were captured using short-time exposures of 60 microm particles suspended in the bioreactor and illuminated using a thin laser sheet. The effects of scaffold fiber lay down pattern and Reynolds number were obtained and correspondingly compared to results obtained from a computational fluid dynamics (CFD) software package. The objectives of this article are twofold: to investigate the hypothesis that there may be an insufficient exchange of medium within the interior of the scaffold when using our non-perfusion bioreactor, and second, to compare the flows within and around scaffolds of 45 degrees and 90 degrees fiber lay down patterns. Scaffold porosity was also found to influence flow patterns. It was therefore shown that fluidic transport could be achieved within scaffolds with our bioreactor design, being a non-perfusion vessel. Fluid velocities were generally same of the same or one order lower in magnitude as compared to the inlet flow velocity. Additionally, the 90 degrees fiber lay down pattern scaffold was found to allow for slightly higher fluid velocities within, as compared to the 45 degrees fiber lay down pattern scaffold. This was due to the architecture and pore arrangement of the 90 degrees fiber lay down pattern scaffold, which allows for fluid to flow directly through (channel-like flow).

Use of fluorescein as a ground water tracer in brackish water aquifers.

A drift and pumpback experiment was conducted in a brackish water sandfill. The sandfill was reclaimed from the sea in the eastern part of Singapore and contains sands with low organic and clay/silt contents. The high salinity in the ground water precludes the use of chloride and bromide as tracers in such an environment, and a field experiment was conducted to assess the viability of using fluorescein as a tracer in brackish water aquifers. Nitrate was used as a second tracer to serve as a check. Initial laboratory studies showed that fluorescence was unaffected over the range of electrical conductivity and pH of the ground water. Results from the field experiment show that fluorescein appears to behave conservatively.

The p53 knowledgebase: an integrated information resource for p53 research.

The p53 tumor suppressor protein plays a central role in maintaining genomic integrity by occupying a nodal point in the DNA damage control pathway. Here it integrates a wide variety of signals, responding in one of several ways, that is, cell cycle arrest, senescence or programmed cell death (apoptosis). Mutations in the tumor suppressor gene tp53, which affects the key transcriptional regulatory processes in cell growth and death, occur frequently in cancer and helps explain why p53 has been called the guardian of the genome. There is a vast body of published knowledge on all aspects of p53's role in cancer. To facilitate research, it would be helpful if this information could be collected, curated and updated in a format that is easily accessible to the user community. To this end, we initiated the p53 knowledgebase project (http://p53.bii.a-star.edu.sg). The p53 knowledgebase is a user-friendly web portal incorporating visualization and analysis tools that integrates information from the published literature with other manually curated information to facilitate knowledge discovery. This includes curated information on sequence, structural, mutation, polymorphisms, protein-protein interactions, transcription factors, transcriptional targets, antibodies and post-translational modifications that involve p53. The goal is to collect and maintain all relevant data on p53 and present it in an easily accessible format that will be useful to researchers in the field.

Effects of cement on redistribution of trace metals and dissolution of organics in sewage sludge and its inorganic waste-amended products.

The suitability of using cement-stabilized sludge products as artificial soils in earth works was evaluated. The sludge products investigated were cemented sludge, cement-treated clay-amended sludge (SS+MC), and cement-treated copper slag-amended sludge (SS+CS). The leachability of lead (Pb), zinc (Zn), copper (Cu), and chromium (Cr) were assessed using the sequential extraction technique, toxicity characteristic leaching procedure (TCLP), NEN 7341 availability test, and column leaching test. The results indicated that Zn leachability was reduced in all the cement-stabilized sludge products. In contrast, Cu was transferred from the organic fraction to the readily leachable phases in the cement-stabilized sludge products and therefore exhibited increased leachability. The increased Cu leachability could be attributed to dissolution of humic substances in the sludge as a result of elevated pH. Good correlation between dissolved organic carbon (DOC) and heavy metal leaching from the cement-stabilized sludge products was observed in the column leaching experiment. Even with a cement percentage as small as 12.5%, calcium silicate hydrate (C-S-H) was formed in the SS+MC and SS+CS products. Inclusion of the marine clay in the SS+MC products could reduce the leaching potentials of Zn, and this was the great advantage of the marine clay over the copper slag for sludge amendment.

Diversity among community isolates of methicillin-resistant Staphylococcus aureus in Australia.

Community methicillin-resistant Staphylococcus aureus (CMRSA) strains are being isolated with increasing frequency around the world. In Western Australia CMRSA are endemic in geographically remote communities and have been found to belong to five different contour-clamped homogeneous electric field (CHEF) electrophoretic patterns. Representatives of each of these CHEF patterns have been compared to CMRSA representative of CHEF patterns from other Australian states and New Zealand. With one exception, all of the isolates were nonmultiresistant and were not resistant to many antimicrobial agents other than the beta-lactams. With one exception, which is not believed to be a CMRSA, all of the isolates harbored a beta-lactamase plasmid. Erythromycin resistance was associated with a 2-kb plasmid. One of the beta-lactamase plasmids was found to be able to acquire additional resistance determinants to become a multiple resistance plasmid. There were 10 multilocus sequence types belonging to eight distantly related clonal complexes of S. aureus. One new sequence type was found. Although most of the CMRSA harbored the type IVa SCCmec, a type IV structural variant was found and two new SCCmec types were identified. Protein A gene (spa) typing revealed two new spa types and, with two exceptions, corresponded to multilocus sequence typing. In contrast to other reports on CMRSA, most of the CMRSA strains studied here did not contain the Panton-Valentine leukocidin genes. The results also demonstrate that nonmultiresistant hospital strains such as UK EMRSA-15 may be able to circulate in the community and could be mistaken for CMRSA based on their resistance profiles.

The use of abciximab in coronary angioplasty--an Asian centre's experience.

BACKGROUND: Abciximab, a monoclonal antibody to platelet glycoprotein IIb/IIIa receptor, has been shown to be effective in reducing ischemic complications after coronary angioplasty in recent trials. However, little is known about its efficacy and safety when used in Asian patients. METHODOLOGY: Based on our abciximab registry, we performed a retrospective analysis of 115 Asian patients who received the antiplatelet agent while undergoing percutaneous coronary intervention in our centre. They constituted 18.4% of the total number of patients undergoing percutaneous revascularisation during the corresponding period. The majority of the patients were males (84%). The mean age of the cohort was 54 and the mean weight was 70 kg. The ethnic composition of the study population was: Chinese 54%, Indians 21%, Malays 19% and Others 6%. All patients received aspirin 100 mg and weight-adjusted heparin before the procedure. Abciximab may be administered on a preplanned basis prior to the procedure or be given as a 'bailout' strategy. RESULTS: There was a high clinical success rate of 95.8% and low incidence of ischemic complications when abciximab was given during coronary angioplasty. There were 0% Q myocardial infarction, 3.3% non-Q myocardial infarction and 0.8% death in our series. Bleeding complications were uncommon at 7.6%, predominantly involving the groin and gingiva. Thrombocytopenia occurred in 5.8% of patients. Abciximab was noted to increase the procedural activated clotting time (ACT) by 38 seconds when given concomitantly with heparin. The mean maximal procedural ACT achieved was 323 +/- 51 seconds. CONCLUSIONS: Abciximab may be used safely and efficaciously in Asian patients undergoing coronary angioplasty. The drug confers protection against ischemic complications during the procedure whether it is administered electively or as a 'bailout'. There is however, a need to redefine the heparin regime for our patients, given the high ACT obtained when abciximab is administered.

Hybrid cardiac revascularisation surgery.

Currently, 3 methods of myocardial revascularisation are available for the treatment of coronary artery disease: i) coronary artery bypass grafting (CABG); ii) percutaneous transluminal coronary angiography (PTCA), and iii) transmyocardial laser revascularisation (TMR). Until recently, these procedures were performed exclusive to one another. We report 2 cases of minimally invasive direct coronary artery bypass grafting with subsequent PTCA, and 1 case of staged PTCA followed by TMR performed at our institution. We discuss the role of hybrid procedures in the current era of treatment of ischaemic heart disease.

Cortical blindness following coronary angiography.

A 53-year-old man developed transient cortical blindness after coronary angiography, which appears to be an adverse reaction to contrast agent. A possible mechanism of this complication is contrast penetration of the blood-brain barrier with direct neurotoxicity to the occipital cortex.

Chronic haemodialysis with PTFE arterio-venous grafts.

BACKGROUND/AIM OF STUDY: End-stage renal failure (ESRF) patients requiring long-term haemodialysis need a durable vascular access. The arterio-venous fistula (AVF) with its long patency rate and low complication profile is usually the first choice procedure for vascular access creation. However when superficial veins are not suitable for AVF creation or have all been exhausted as a result of repeated AVF procedures, arterio-venous grafts (AVG) using polytetraflouroethylene (PTFE) to bridge arteries and veins is an alternative for provision of continued vascular access for haemodialysis. This study is a review of our experience in using PTFE AVGs for vascular access in patients requiring chronic haemodialysis. METHODS AND MATERIALS: A retrospective review was done on 92 grafts in 77 patients placed by 3 vascular access surgeons at the Singapore General Hospital from January 1989 to December 1994. RESULTS: There were 58 female and 19 male patients with a median age of 43 years (range 15-76 years). Twelve patients (16%) were diabetic and 6 patients (8%) had systemic lupus erythematosis requiring long-term steroids. Seventy-three percent of patients had up to 2 previous AVF creations before placement of AVG over the forearm (64%), upper arm (23%) or thigh (6.5%). Complications include graft infection (19), pseudoaneurysm formation (10), graft thrombosis (24), steal syndrome (1), venous congestion (1) and venous end stenosis (1). Diabetic status and long-term steroid therapy did not significantly increase the incidence of graft infection. The patency rates at 24 months and 36 months were 77% and 58% respectively. However serviceability rates were 61% at 2 years and 38% at 3 years mainly due to infective complications. CONCLUSION: PTFE AVGs offer reasonable patency and serviceability rates as a vascular access modality but in view of their complication profile, the native vein arteriovenous fistula should continue to be the first choice procedure for vascular access in patients requiring chronic haemodialysis.