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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Pig mucus as an inhibitory agent of HIV-1

Pillay, Santhoshan Thiagaraj January 2017 (has links)
The Human Immunodeficiency Virus (HIV) epidemic still poses a problem with approximately 2 million new infections reported worldwide in 2014. New strategies are required to alleviate this burden. Our laboratory has previously shown that crude saliva and purified mucins from cervical plug mucin, saliva and breast milk inhibit HIV-1 infection in vitro. This project investigates purified mucins sourced from pig and horse mucus, as an alternative and abundant source of material for anti-HIV-1 research. Pig gastric and cervico-vaginal mucus was collected and stirred overnight in 6M guanidine hydrochloride with 10mM Na₂HPO4, 10mM EDTA, 1mM PMSF and 5mM NEM. Gastric and cervicovaginal mucus was purified by density gradient ultracentrifugations in CsCl at 105 000g for 48 hours, twice, and mucin rich fractions were separated by size exclusion column chromatography. Mucin-rich materials eluting in the void volume (V₀) were reduced with 10mM dithithreitol (DTT) or subjected to proteolysis with trypsin. Pig saliva was collected in 0.2M NaCl:0.02% sodium azide and horse saliva (due to its viscous nature) was collected and stirred overnight in 6M guanidine hydrochloride with 10mM Na₂HPO4, 10mM EDTA, 1mM PMSF and 5mM NEM. Pig and horse saliva samples underwent size exclusion column chromatography, where the V₀ fractions of both were purified with one density gradient ultracentrifugation and then dialysed and freeze dried, after which aliquots were treated with either DTT or trypsin. At every stage of purification, lyophilized aliquots of all mucin sources were tested on a luciferase based replication defective HIV neutralization assay on a CD4 expressing HeLa cell line. Luciferase expression quantified as relative light units by a luminometer was used to calculate percentage neutralization. Log dose response curves were constructed to extrapolate the half maximal inhibitory concentrations (IC₅₀) on GraphPad Prism. Samples were tested on an MTT cell toxicity assay. Pig gastric and cervicovaginal mucins were added to a simulated vaginal fluid to make gels (at a concentration of 30mg of mucin per ml of buffer). These gels were tested on the neutralization, MTT assays and the pig gastric mucin gel then underwent particle tracking and nanoparticle diffusion assays at varying pH. Pig gastric and cervicovaginal mucin showed good inhibition and low toxicity, with pig gastric mucin V₀ having the best IC₅₀ (1.668μg/ml). Pig and horse saliva showed inhibition but low cell viability. Pig gastric and cervicovaginal mucin gels exhibited good IC₅₀'s but pig gastric mucin had the best neutralization and lowest toxicity (PGM in Gel Solution 4 IC₅₀: 20.23μg/ml). HIV particle tracking and nanoparticle diffusion assays showed that the pig gastric mucin gel inhibited HIV-1 at low pH and existed as a soft gel. This project shows the efficacy of pig gastric mucin to possibly being a component of an anti-HIV-1 vaginal microbicide.
2

Immunohistochemical identification of mismatch repair gene deficit and its clinico-pathologic significance in young patients with colorectal cancer

Hameed, Muhammad Fayyaz January 2005 (has links)
Includes bibliographical references (leaves 43-52). / An immunohistochemical technique is used in this study to detect mismatch repair deficit in young patients with colorectal cancers. Ninety three patients who were 45 years of age or younger at the time of diagnosis of colorectal cancer were studied.
3

The Determinants of Health Care Costs in Older Adults Undergoing Non-Elective Abdominal Surgery

Bailey, Jonathan 23 July 2013 (has links)
Health care spending in Canada has been increasing faster than the rate of gross domestic product (GDP). A disproportionate amount of the health care spending is allocated to care of older adults. Non-elective abdominal surgery is an expensive area of care for older adults. Despite this, the factors associated with cost in this patient population remain unclear. OBJECTIVES The primary objective of this study was to estimate the association between perioperative factors (age, American Society of Anesthetists (ASA) classification, operative severity (OS), frailty index (FI), complication severity) and health care costs among older adults undergoing non-elective abdominal surgery. The secondary objectives were: 1. to provide a comprehensive description of costs based on patient-level resource utilization; and 2. to examine the relationship between hospital costs and adverse events (non-fatal complication severity, mortality, and change in living arrangement). METHODS This study was an observational prospective cohort study. Over a 15 month period all patients 70 years or older who underwent non-elective abdominal surgery at the QEII Health Sciences Centre, Nova Scotia, were enrolled. Data were collected on patient demographics, investigations, treatments, and outcomes. Direct hospital health care costs (2012 $CAD) were calculated by tabulating patient-level resource use and assigning specific costs. The association between five perioperative factors and costs were analyzed using univariate non-parametric tests and multiple linear regression. The associations between adverse events and costs were assessed using univariate non-parametric tests and multiple linear regression. RESULTS During the study period, 212 patients who underwent abdominal surgery (median age 78 years (range 70-97)) were enrolled. The median costs of care were $9,166 (range $1,993-$104,403). The largest proportions of spending were non-procedural costs (65% [$2,176,875]) and intensive care costs (16% [$554,523]). The perioperative factors ASA classification (p=0.0010), OS (p<0.0001), FI (p=0.0002) and complication severity (p<0.0001) were all independently associated with health care costs, while age was not (p=0.5330). The following adverse events were independently associated with health care costs: non-fatal complication severity (p<0.0001), change in living arrangement (p=0.0002), and mortality (p=0.0337). Non-fatal complications had the strongest association with hospital costs (standardized β coefficient = 0.3931). CONCLUSION Four perioperative factors (ASA, OS, FI and complication severity) are associated with costs; therefore, representing a potential cost prediction model for this patient group. This study is important for health care administrators, identifying targets for cost reduction. Cost reduction strategies and research should concentrate on mitigating or preventing complications and high cost areas, such as non-procedural costs and intensive care, in order to achieve cost savings.
4

Dyslipidaemic pancreatitis : clinical assessment and analysis of disease severity and outcomes.

Anderson, Frank. January 2006 (has links)
Introduction: The relationship between pancreatitis and dyslipidaemia is unclear and has never been studied in a South African context. Patients and methods: A prospective evaluation of all admissions with acute pancreatitis to a regional hospital general surgical service was performed to ascertain its relationship to dyslipidaemia. Aetiology was determined by history and ultrasound assessment. Disease severity was assessed using a modified Imrie score and an organ failure score. Body mass index was calculated. A lipid profile was obtained. Abnormal profiles were repeated. Secondary causes of dyslipidaemia were noted. A comparison of the demographic profile, aetiology, disease severity scores, complications and deaths were made in relationship to the lipid profiles. Results: From June 2001 to May 2005, there were 230 admissions, of whom 31% were women and 69% men. The median age was 38 years(range 13- 73). The pancreatitis was associated with alcohol in 146(63%), gallstones in 42(19%) and idiopathic in 27(12%). The amylase was significantly higher with a gallstone aetiology (p / Thesis (MMedSc)-University of KwaZulu-Natal, 2006.
5

Risk assessment for renal injury post aortic surgery using new and more sensitive markers of renal injury.

Pillay, Woolagasen Ramalingham. January 2003 (has links)
Renal failure in patients undergoing Aortic surgery is associated with a poor outcome. The shortcomings of serum creatinine for measuring renal function are well documented. We examined the value of alternative markers in diagnosing and predicting renal damage in patients undergoing abdominal aortic surgery and those exposed to intravascular contrast media. Cystatin C lacks some of the reservations associated with serum creatinine when used as a marker of glomerular filtration rate. The protease inhibitor alpha-glutathione Stransferase (a-GST) is recovered in urine after injury to proximal tubular cells. Urine microalbumin is a marker of glomerular permeability. Together we used all four assays to detect and characterize the nature of renal injury after surgery and contrast exposure. Cystatin C had a marginally better sensitivity than serum creatinine at detecting baseline renal impairment. It also showed earlier changes in individual patients whose renal dysfunction deteriorated over time. The urinary markers showed an earlier significant rise after the onset of surgery when compared to serum markers, but only a-GST rose significantly after contrast exposure. Patients undergoing a supra-renal cross-clamp showed significantly higher a-GST levels (and not the other three markers) when compared to the infra-renal group. Cystatin C appears to have better sensitivity and specificity for predicting the need for dialysis in patients undergoing surgery. Peak serum creatinine and cystatin C after contrast exposure show good correlation with peak values after surgery. Cystatin C is equivalent to and may be better than serum creatinine in detecting preexisting and deteriorating renal impairment. Although the urinary assays are earlier markers of renal injury, their clinical significance needs to be determined. Elevation in creatinine and cystatin C after contrast exposure parallel those after surgical intervention and may be helpful in selecting out high-risk patients prior to surgery. / Thesis (M.Med.Sc.)-University of Natal, 2003.
6

The influence of diabetes mellitus on early outcome following vascular surgical interventions.

Mulaudzi, Thanyani Victor. January 2012 (has links)
Objective. To assess the influence of diabetes mellitus on early morbidity and mortality following open vascular surgical interventions. Methods. Clinical data on patients subjected to open vascular surgical procedures over a 5 year period at the Durban Metropolitan Vascular Service was culled from a prospectively maintained computerized database. They were divided according to the type of surgical procedure performed. These were open abdominal aortic surgery, peripheral bypass surgery, lower extremity major amputation and carotid endarterectomy. They were further subdivided into 2 groups, diabetic and non-diabetic. Results. 1104 charts were analysed. There were no significant differences in demographics and risk factors between the two groups. 273 patients had open abdominal aortic surgery. 217 (79%) were non-diabetic. diabetic patients had significantly higher incidence of myocardial infarction (p=0.00001) (6 of 6 patients), graft sepsis (p=0.000001) (7 of 7 patients) and mortality rate (p=0.0335) (5 of 10 patients). 337 patients had peripheral bypass procedures. 204 (60%) of these were non-diabetic. There was a high prevalence of smokers among non-diabetics and of hypertension among diabetics. Diabetic patients had a preponderance of graft infection (p=0.0015) (15 of 20 patients) and cardiovascular complications (p=0.0072) (7 of 8 patients). 230 patients had lower extremity major amputations, 81 (35%) were diabetic and 149 (65%) non-diabetic. Myocardial infarction and death (6 of 8 patients each) were significantly higher among diabetics (p =0.04). 264 patients had carotid endarterectomy, 170 (64%) being non-diabetic. The surgical outcome was similar between the two groups. Conclusions. This is retrospective study and as such it has some its limitations. Not all patients might have been included in the study and some of the information might have been lost. The numbers in this study are large and these limitations would appear not to have influenced the outcome of this study. This study has shown that diabetes mellitus had diverse influence on the early outcome following different vascular surgical procedures. Diabetes mellitus significantly increased the incidence of graft sepsis among those who had aorto-bifemoral bypass and peripheral bypass procedures. The incidence of peri-operative cardiovascular morbidity was significantly increased among diabetics who had peripheral bypass procedures, open abdominal aortic surgery and lower extremity major amputations. Diabetes mellitus had no influence on the surgical outcome following carotid endarterectomy. / Thesis (M.Med.)-University of KwaZulu-Natal, Durban, 2012.
7

An anatomical exploration into the variable patterns of the venous vasculature of the human kidney.

Satyapal, Kapil Sewsaran. January 1993 (has links)
In clinical anatomy, the renal venous system is relatively understudied compared to the arterial system. This investigation aims to clarify and update the variable patterns of the renal venous vasculature using cadaveric human (adult and foetal) and Chacma baboon (Papio ursinus) kidneys and to reflect on its clinical application, particularly in surgery and radiology. The study employed gross anatomical dissection and detailed morphometric and statistical analyses on resin cast and plastinated kidneys harvested from 211 adult, 20 foetal and 10 baboon cadavers. Radiological techniques were used to study intrarenal flow, renal veins and collateral pathways and renal vein valves. The gross anatomical description of the renal veins and its relations were confirmed and updated. Additional renal veins were observed much more frequently on the right side (31 %) than previously documented (15.4%). A practical classification system for the renal veins based on the number of primary tributaries, additional renal veins and anomalies is proposed. Detailed morphometric analyses of the various parameters of the renal veins corroborated and augmented previous anatomical studies. Contrary to standard anatomical textbooks, it was noted that the left renal vein is 2.5 times the length of its counterpart and that there are variable levels of entry of the renal veins into the IVC. Justification for the distal segment of the left renal vein to be termed the surgical trunk, and the proximal segment to be the homologue of the right renal vein is presented. Radiological investigations demonstrated a non-segmental and non-lobar intrarenal venous architecture, an absence of renal vein valves and extensive venous collaterals centering on the left renal vein. These collateral channels, present in the foetus, and persisting in the adult, may be operative and of clinical significance in pathological states. No sex differences and no race differences of note were recorded in this study. The Chacma baboon displayed similar intra-renal venous anatomy. The applied clinical anatomy of these findings with particular regard to renal surgery and uro-radiology is emphasised. / Thesis (M.D.)-University of Natal, 1993.
8

Uma associação científica no interior das Gerais: a Sociedade de Medicina e Cirurgia de Juiz de Fora (SMCJF) - 1889-1908 / A scientific association in the Gerais: the Sociedade de Medicina e Cirurgia de Juiz de Fora (SMCJF) - 1889-1908

Lana, Vanessa January 2006 (has links)
Made available in DSpace on 2012-05-07T14:48:02Z (GMT). No. of bitstreams: 2 license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5) 000025.pdf: 723699 bytes, checksum: c2c8f70946f35d0d4bee77090bef3a19 (MD5) Previous issue date: 2006 / Centra-se na análise da Sociedade de Medicina e Cirurgia de Juiz de Fora no período compreendido entre os anos de 1889 a 1908. O estudo leva em conta a atuação dos personagens que deram luz a esta história, em outras palavras, as ações dos membros da SMCJF.
9

An evaluation of the use of transcutaneous oxygen pressure measurement in the non-invasive vascular laboratory : with special reference to selection of amputation level.

Mars, Maurice. January 2001 (has links)
Transcutaneous oxygen pressure measurement (TCp02) using a miniaturised Clarke electrode and a heating thermistor was developed independently by Huch et al and Eberhardt et al in 1972. After its initial use to non invasively monitor arterial partial pressure (Pa02) in neonates it was proposed as a useful test of skin blood flow and possibly amputation wound healing level selection in patients with peripheral vascular disease. Unfortunately a wide range of predictive values emerged with some authors reporting amputations healing when the TCp02 value was 0 mmHg. The investigation, while still considered useful, has not gained widespread support. This study investigates the use of TCp02, establishes a value for the use of the TCp02 Index to predict amputation wound healing potential and examines the hypothesis that the use of the TcpO Index to select amputation level can reduce patient morbidity and mortality. The literature is reviewed and a series of studies evaluating TCp02 use, undertaken in the Durban Metropolitan Vascular Service Non-Invasive Laboratories, are presented. TCp02 measurements were performed in a standardised manner with the subject supine breathing room air. Measurements were taken at fixed sites, on the mid dorsum of the foot (Foot), 10 cm distal to the tibial tuberosity and 2 cm lateral to the anterior tibial margin (BKA), 10 cm proximal to the patella in the midline (AKA) and on the chest in the mid-clavicular line. A TCp02 Index, the limb to chest ratio was defined. TCp02 data derived from control subjects asymptomatic of peripheral vascular disease were shown to be similar to age matched pooled data derived from the literature. In patients with peripheral vascular disease, absolute TCp02 and the TCp02 Index were shown to fall from proximal to distal sites and again were no different to pooled data derived from the literature. Based on presenting symptoms, the fall in TCp02 and the TCp02 Index was significant from proximal to distal sites. The reduction in absolute TCp02 and the TCp02 was also related to the most distal pulse present. TCp02 values were found to be no different in patients with peripheral vascular disease with or without diabetes. When comparing TCp02 and the TCp02 Index with Doppler pressure measurements at the Popliteal artery and at the foot, and the Doppler ankle brachial index (ABI), Doppler derived data were significantly higher in diabetic patients than in non-diabetic patients. No differences were noted in TCp02 data. TCp02 was compared with the 133Xe radio-isotope skin washout test. The best correlation was (r = 0.46) was obtained with a logarithmic curve y = 10.862Ln(x) + 38.751. TCp02 was compared with antibiotic concentrations (Cefoxitin) in muscle obtained from the site of amputation and the Cefoxitin Index, the ratio of muscle antibiotic concentration to plasma concentration, as an indication of the relationship of skin TCp02 to muscle blood flow. A significant correlation was shown between the Cefoxitin Index and TCp02 (r = 0.67, p = 0.035) and the TCp02 Index (r = 0.64, P = 0.045), suggesting that skin oxygen delivery may reflect muscle antibiotic delivery and hence blood flow. TCp02 and the TCp02 Index were compared with heated and unheated laser Doppler fluxmetry (LDF) in 35 patients undergoing amputation wound healing assessment. Significant correlations were shown between heated LDF, heated LDF Index and the TCp02 Index (r = 0.63 and r = 0.69, P < 0.0001). TCp02 Index values of 0.5 and 0.55 showed an accuracy of 96.2 % in predicting amputation outcome while LDF values of 3, 4 and 5 arbitrary units gave an accuracy of 88.5 %. Using receiver operator curves, a TCp02 Index of 0.55 was shown to be the best test. Over the years 1987 and 1988, TCp02 data were gathered on 193 patients undergoing lower limb amputation for peripheral vascular disease. Information on the outcome of the amputation was available for 152 amputations. Circumstances which might result in a reduced pre-operative TCp02 reading were identified and criteria were set for the use of TCp02 to predict amputation wound healing potential. 122 amputations which met the defined entry criteria were available for evaluation. A TCp02 Index of 0.50 gave a definitive predictive value below which no amputation healed. Similarly no amputation with an absolute TCp02 of less than 27 mmHg healed. Receiver operator characteristic curves showed the TCp02 Index to be a better test than absolute TCp02. A TCp02 Index of 0.55 was shown to have the best sensitivity of96.7 %, with a specificity of79.8 % and an accuracy of 90.2 %. When introduced to clinical practice, correct use of the TCp02 Index of 0.55 resulted in a reduction in amputation revision rate from 40.3 % in 1987, to 8.2 % in 1990. Initially some surgeons felt that the TCp02 Index predicted amputation wound failure at distal sites at which healing could be expected on clinical criteria, and chose amputate at sites with a TCp02 Index value less than 0.55. These amputations failed to heal. As surgeons gained confidence in the test, they chose to follow the TCp02 data more often and the percentage of amputations performed at sites predicted by the TCp02 Index to fail , fell from 35.5 % in 1987 to 6.6 % in 1990. Over a 15 year period at King Edward VIII Hospital, the amputation revision rate has fallen from an average of 32.7 % in the first five years when Tcp02 data were not available to the surgeon, to 21.4 % and 22.9 % in the two subsequent 5 year periods when Tcp02 data were available. The mortality rates were unchanged. The decline in revision rates was less than expected and relates to the fact that approximately only 42 % of patients requiring amputation undergo the test. This is because it is time consuming and available only during weekday office hours. These studies have confirmed the usefulness of Tcp02 measurement in the non-invasive vascular laboratory. The index is shown to be superior to absolute Tcp02 as a predictive test of amputation wound healing. The introduction of several criteria to define when Tcp02 use is appropriate has refined the investigation and made it clinically useful in our setting. A Tcp02 Index of 0.55 in the appropriate patient is a useful test to predict amputation wound healing and its use has resulted in reduced patient morbidity and mortality, confirming the hypothesis tested. / Thesis (M.D.)-University of Natal, 2001.
10

A comparative study evaluating the role of a prostaglandin (ripoprostil) and a H2 antagonist ranitidine in oesophageal mucosal protection against reflux induced oesophagitis.

Goga, Anver. January 1997 (has links)
Thesis (M.Med.)--University of Natal, Durban, 1997.

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