466 research outputs found

    A 10-Year Prospective Evaluation of Balloon Tube Tamponade and Emergency Injection Sclerotherapy for Actively Bleeding Oesophageal Varices

    Get PDF
    During a 10 year study period 234 patients were admitted on 371 occasions with a total of 566 acute variceal bleeding episodes. Of these, 173 patients had 343 variceal bleeds which required balloon tamponade to achieve initial control of bleeding during 229 admissions and were then referred for emergency injection sclerotherapy. Sixty-eight percent of these patients had alcoholic cirrhosis and 42% were poor risk Grade C patients. Injection sclerotherapy was performed initially using the rigid Negus oesophagoscope under general anaesthesia and later using the fibreoptic endoscope under light sedation. Definitive control of variceal bleeding was achieved with sclerotherapy during 197 hospital admissions (92%). Of the 17 failures of emergency sclerotherapy, 4 patients died from uncontrolled bleeding and 13 patients underwent major surgical intervention. Definitive control of variceal bleeding was achieved with a single injection treatment in 138 hospital admissions (70%). Complications were mostly of a minor nature and occurred at a rate of 6% per injection treatment. The overall hospital admission mortality was 36%. The majority of patients died due to liver failure. The mortality in patients who required 4 injection treatments to control variceal bleeding was 71%. Injection sclerotherapy is proposed as the emergency treatment of choice for patients whose variceal bleeding continues or recurs after initial conservative management. Patients whose variceal bleeding is not controlled by 2 injection treatments require more major emergency surgery

    Modified polysaccharide-based particles for strengthening paper

    Get PDF
    Thesis (PhD (Process Engineering))--University of Stellenbosch, 2010.ENGLISH ABSTRACT: The ongoing trend in papermaking industries is to lower production costs by increasing the low cost filler content in the sheets. However, the disruption of inter-fibre bonding is accompanied by a deterioration of paper stiffness and mechanical properties if filler content exceeds 18 wt%. Polysaccharide solutions, such as starch, are often used as a low cost biodegradable additive to improve internal sheet strength when added to the wet-end of production. The amount of starch that can be added is however limited as only a small percentage will be retained in the paper web. A dual additive multifunctional polysaccharide system was developed to allow higher filler loading levels without detrimental deterioration in paper properties. In order to achieve a larger surface area for fibre/filler interaction and to reduce drainage losses, at least one of these additives was in particulate form. Anionic, cationic, and unsaturated derivatives were prepared using sodium monochloroacetate, 3-chloro-2-hydroxypropyltrimethylammonium chloride, and allyl bromide, respectively. The degree of substitution was determined by 1H-NMR spectroscopy and back titration methods and the interaction of the ionic modified derivatives with paper components was determined using fluorescence microscopy. Anionic modified polysaccharide particles were prepared using techniques such as macrogel ultrasonification, water-in-water emulsification, and in-situ cross-linking and carboxymethylation of granular starch. A process of adding sequential layers of oppositely charged polyelectrolyte layers onto the filler particles was also investigated. A novel approach of preparing modified particles with tailored size and distribution using microfluidics was studied and modelled using response surface methodology. Hand sheets were prepared using the dual additive system and improvements in stiffness, tear resistance, breaking length, and folding endurance were observed. The modified granular maize starch particles had a pre-eminent effect on improving stiffness at higher filler loadings (14% improvement at 30 wt% filler loading), while bulky particles prepared using microfluidics showed a more consistent improvement (between 6% and 10%) across the loading range. Overall improvements gained by the introduction of multi-layered soluble polymers onto fillers suggest that the introduction of nanotechnology to the papermaking process should be of potential benefit to the industry. Furthermore, the dual additive system developed during the course of this study should also be tested on a continuous pilot plant papermaking process.AFRIKAANSE OPSOMMING: Die papierindustrie neig voortdurend daarna om produksiekostes te verlaag deur die persentasie lae koste vulstof wat gebruik word te verhoog. Aangesien die vulstof vesel kontak belemmer, gaan hoër vlakke (> 18 wt%) egter gepaard met ’n verlaging in papier styfheid en meganiese eienskappe. Polisakkaried oplossings, soos byvoorbeeld stysel, word dikwels gebruik as lae koste vergaanbare bymiddel om papier intern te versterk wanneer dit voor die vormingsproses bygevoeg word. Slegs ’n beperkte hoeveelheid stysel word egter behou in die papier matriks en oormatige oplossings ontsnap tydens dreinering in die afvalwater. ’n Dubbele multi-funksionele polisakkaried bymiddelsisteem was ontwikkel wat ongewensde verwakking in papiereienskappe verminder tydens vulstof verhogings. Ten minste een van die bymiddels was in partikelvorm om sodoende ’n groter oppervlak te bied vir vesel/vulstof interaksie en om dreineringsverliese te verminder. Anioniese, kationiese, sowel as onversadigde derivate was berei deur onderskeidelik gebruik te maak van natrium monochloroasetaat, 3-chloro-2-hidroksiepropieltrimetielammonium chloried, en alliel bromied. Die graad van substitutiese was bepaal met behulp van 1H-KMR spektroskopie sowel as titrasie tegnieke terwyl die ioniese interaksie van die gemodifiseerde stysels met die papierkomponente ondersoek was met behulp van fluoressensie mikroskopie. Anioniese polisakkaried partikels was berei met tegnieke soos makro-jel ultrasonifikasie, water-in-water emulsifikasie, en in-situ kruisbinding en karboksiemetielasie van stysel granulate. ’n Proses was ook ondersoek waar vulstof partikels omhul was in verskeie lae poliëlektroliet oplossings. ’n Nuwe benadering was toegepas waar gemodifiseerde partikels met voorafbepaalde grootte en verspreiding berei is deur gebruik te maak van mikrofluïdika en gemodelleer met behulp van oppervlakte ontwerp metodeleer. Papier toetse was uitgevoer met die bymiddelsisteem en algehele verbetering in styfheid, skeurweerstand, breeklengte, en voulydsaamheid is waargeneem. Die gemodifiseerde stysel granulate het die grootste verbetering in styfheid by hoë vulstofladings getoon (14% verbetering by 30 wt% vulstoflading) terwyl die groter mikrofluïdika-bereide partikels algehele verbetering (tussen 6% en 10%) getoon het oor die hele vulstoflading reeks. Die verbeteringe in styfheid sowel as meganiese eienskappe van papier voorberei met poliëlektroliet omhulde vulstof toon dat aanwending van nanotegnologie in hierdie bedryf potensieel voordelig kan wees. Opskalering van die polisakkaried bymiddels ontwikkel gedurende hierdie studie behoort uitgevoer te word vir verdere toetse op ’n kontinue papier loodsaanleg

    Statin therapy in critical illness : an international survey of intensive care physicians' opinions, attitudes and practice

    Get PDF
    Background Pleotropic effects of statins on inflammation are hypothesised to attenuate the severity of and possibly prevent the occurrence of the host inflammatory response to pathogen and infection-related acute organ failure. We conducted an international survey of intensive care physicians in Australia, New Zealand (ANZ) and United Kingdom (UK). The aims of the survey were to assess the current prescribing practice patterns, attitudes towards prescribing statin therapy in critically ill patients and opinions on the need for an interventional trial of statin therapy in critically ill patients. Methods Survey questions were developed through an iterative process. An expert group reviewed the resulting 26 items for face and content validity and clarity. The questions were further refined following pilot testing by ICU physicians from Australia, Canada and the UK. We used the online Smart SurveyTM software to administer the survey. Results Of 239 respondents (62 from ANZ and 177 from UK) 58% worked in teaching hospitals; most (78.2%) practised in ‘closed’ units with a mixed medical and surgical case mix (71.0%). The most frequently prescribed statins were simvastatin (77.6%) in the UK and atorvastatin (66.1%) in ANZ. The main reasons cited to explain the choice of statin were preadmission prescription and pharmacy availability. Most respondents reported never starting statins to prevent (65.3%) or treat (89.1%) organ dysfunction. Only a minority (10%) disagreed with a statement that the risks of major side effects of statins when prescribed in critically ill patients were low. The majority (84.5%) of respondents strongly agreed that a clinical trial of statins for prevention is needed. More than half (56.5%) favoured rates of organ failure as the primary outcome for such a trial, while a minority (40.6%) favoured mortality. Conclusions Despite differences in type of statins prescribed, critical care physicians in the UK and ANZ reported similar prescription practices. Respondents from both communities agreed that a trial is needed to test whether statins can prevent the onset of new organ failure in patients with sepsis

    Geographic variation and plasticity in climate stress resistance among southern African populations of Ceratitis capitate (Weidemann) (Diptera: Tephritidae)

    Get PDF
    Traits of thermal sensitivity or performance are typically the focus of species distribution modelling. Among-population trait variation, trait plasticity, population connectedness and the possible climatic covariation thereof are seldom accounted for. Here, we examine multiple climate stress resistance traits, and the plasticity thereof, for a globally invasive agricultural pest insect, the Mediterranean fruit fly, Ceratitis capitata (Wiedemann) (Diptera: Tephritidae). We also accounted for body size and population genetic connectivity among distinct populations from diverse bioclimatic regions across southern Africa. Desiccation resistance, starvation resistance, and critical thermal minimum (CTmin) and maximum (CTmax) of C. capitata varied between populations. For thermal tolerance traits, patterns of flexibility in response to thermal acclimation were suggestive of beneficial acclimation, but this was not the case for desiccation or starvation resistance. Population differences in measured traits were larger than those associated with acclimation, even though gene flow was high. Desiccation resistance was weakly but positively affected by growing degree-days. There was also a weak positive relationship between CTmin and temperature seasonality, but CTmax was weakly but negatively affected by the same bioclimatic variable. Our results suggest that the invasive potential of C. capitata may be supported by adaptation of tolerance traits to local bioclimatic conditions

    DIE ONTWIKKELING VAN ’N BEMARKINGSTRATEGIE VIR CENTURION GEMEENSKAPSDIENS

    Get PDF
    Centurion Community Services (CCS), a social service agency situated in Lyttelton,Pretoria, was founded in February 1999. The geographical area where services were rendered over the past four years has been transformed from a once quiet rural scene to a densely populated urban area. The founding of CCS testifies to a pro-active step to address anticipated social problems associated with urbanisation.A qualitative study was launched with the aim to assess the community’s perception concerning CCS and whether this service is able to fulfil the needs and wants of the community with a view of development of guidelines for a consumer-based marketing strategy.A schedule covering the seven critical areas of decision-making in a marketing strategy had been developed and utilised as a data collection instrument to collect data from respondents, who have all been beneficiaries in one way or another of this service.It was found that a strategic planning process should be implemented in order to obtain clarity regarding the vision and mission of the organization; a marketing plan (which includes the strategic analysis, the SWOT analysis, marketing objectives and marketing strategy) should be applied extensively. A number of recommendations regarding critical decision making areas were also formulated

    Long-Term Management After Variceal Bleed — The Current Role of Sclerotherapy

    Get PDF
    While injection sclerotherapy has been accepted as the treatment of choice for acute variceal bleeding, its role as a definitive long-term treatment modality has not yet been clearly defined. This paper will critically analyse the current status of this technique, now widely used, and a comparison will be made with conventional medical management. The review will be based on the 10 years' Cape Town experience and the published series on this subject. A long-term management strategy will also be discussed
    • …
    corecore