Search PubMed⌕ Search

Biomedical subjects

G Smart

Publications and source records attributed to G Smart.

At least 19 recordsLinked to original sources

Survival analysis of liver transplant patients in Canada 1997-2002.

UNLABELLED: Liver transplantation is an important health care issue for Canadians. Very few studies have assessed survival and determinants of survival in liver transplant patients in Canada. METHODS: We carried out an epidemiological analysis of 1 year survival and determinants of 1 year survival in liver transplant patients, using Canadian Organ Replacement Registry data (1997-2002). Survival curves were plotted by the Kaplan-Meier method. Cox proportional hazards analysis was applied to evaluate hazard ratios with different age groups, gender, ethnicity, blood groups, donor type, pretransplantation medical status, and HBV infection status. RESULTS: A total of 1164 liver transplant patients were included in the analysis. One-year survival rate was 84.7%. Male recipients had a 21% higher risk of developing organ failure than females. Recipients over 60 years of age had a 5% lower survival probability in comparison with recipients below 20 years of age. Pacific Islanders and Aboriginals had 32% and 9% lower survival probabilities, respectively, in comparison with Caucasians. Type B blood recipients had a 12% higher survival probability, whereas type AB blood recipients had a 7% lower survival probability compared with type O blood recipients. Twenty-six live organ recipients had 40% higher survival probabilities than 1138 cadaveric organ recipients. Patients with fulminant hepatitis (status 3F) had the highest survival, while patients with fulminant failure in ICU with intubation/ventilation (status 4F) had the lowest survival. One hundred sixty-seven recipients with positive HBsAg antigen showed 10% lower survival probability than 997 cases with negative HBsAg antigen. CONCLUSION: In Canada, the first year survival rate is about 85%, which is comparable with other industrialized countries. Type of donor organs and recipient gender, ethnicity, ABO blood group, pretransplantation medical status, and HBV infection status had significant affects on the recipient survival.

Canada↗

Epidemiological study of hepatitis B virus infection in Manitoba, Canada, 1992-2003.

In comparison with other Canadian provinces and most Western countries, the province of Manitoba maintains a different vaccination policy for hepatitis B. This policy provides selective antenatal screening for hepatitis B in women and an inoculation program for hepatitis B vaccination for fourth-grade pupils. There has been increasing concern for this policy with regard to its influence on secular trends of acute hepatitis B incidence in Manitoba. This created a need to summarise the epidemiological characteristics of hepatitis B virus (HBV) infection in Manitoba and to allocate finances and human resources for future prevention programs. The Cadham Provincial Laboratory in Winnipeg, a Canadian Public Health Laboratory, is responsible for testing all specimens for diagnosis of various common infectious diseases in Manitoba. During the period from 1 January 1992 to 31 December 2003, a total of 285,946 clinical specimens were submitted to this laboratory, which confirmed 310 cases of acute HBV and 7,556 cases of chronic HBV infection. A total of 18,168 individuals were identified as having vaccine-induced immune status. The incidence rate of acute HBV infection has significantly decreased from 6.52/100,000 person-years in 1996 to 0.86/100,000 person-years in 2003. Annual prevalence rates of chronic HBV infection in Manitoba increased slightly from 42.96 cases/100,000 population in 1992 to 71.47 cases/100,000 population in 2003. Incidence rates were generally higher in men than in women at all age groups, with values of 2.65 and 1.65 per 100,000 population, respectively (chi-square=15.768, p value <0.001). The highest incidence rate for both males and females was observed in the age group 30-34 years. The North Eastman and Winnipeg Regional Health Authorities showed significantly higher incidence rates of acute hepatitis B compared with the other nine Regional Health Authorities. Selective hepatitis B vaccination programs for children in Manitoba had achieved the greatest success in the prevention of vertical and horizontal transmission. There is an urgent need to develop cost-effective harm-reduction strategies for hepatitis B prevention among adults (aged 30-34) and groups at risk in Manitoba.

Adolescent↗

The use of 188Re to treat in-stent re-stenosis of coronary arteries.

A pilot study has been conducted in which coronary arteries subject to re-stenosis after angioplasty and stenting have been irradiated following further angioplasty. The method of irradiation has been to use radioactive 188Re in an angioplasty balloon. This paper considers all aspects of the procedure including elution of the rhenium from a tungsten/rhenium generator, its concentration, dispensing and safe delivery to the patient using specially designed equipment to reduce staff doses and radioactive spills. In the pilot study of 28 lesions in 26 patients only 1 was recorded as having angiographic re-stenosis in the treated region at 6 months although 4 other patients had edge re-stenosis. This represents less than 18% re-stenosis in a population that would have been expected to exhibit at least 50% re-stenosis at 6 months. A total of 72 patients have been treated either in the pilot study or a subsequent trial. In only one case has a minor spill of radioactivity occurred and in no case has the balloon burst. Radiation doses to staff are approximately 20 microSv per procedure and are therefore not of serious consequence. It is concluded that this procedure is safe, feasible and effective in reducing in-stent re-stenosis.

Angioplasty, Balloon, Coronary↗

Gnotobiological study of infective juveniles and symbionts of Steinernema scapterisci: A model to clarify the concept of the natural occurrence of monoxenic associations in entomopathogenic nematodes.

Gnotobiology of Steinernema scapterisci and bacteriological study of its symbiont confirmed that this nematode harbors a symbiotic species of Xenorhabdus, as do other Steinermena species. Based on phenotypic and 16S rDNA data, this Xenorhabdus strain UY61 could be distinguished from other Xenorhabdus species. Bacteria reported previously as being associated with this nematode and belonging to several other genera were probably contaminating bacteria located in the intercuticular space of the infective juveniles (IJs). These bacteria were detrimental to nematode reproduction in Galleria mellonella. Axenic S. scapterisci and its symbiont Xenorhabdus strain UY61 alone were not pathogenic to G. mellonella. The combination of both partners reestablished the pathogenicity of the complex toward G. mellonella. This combination also gave the best yields of IJs when produced in this insect and in vitro production on artificial diet.

Animals↗

Seroprevalence of Helicobacter pylori, incidence of gastric cancer, and peptic ulcer-associated hospitalizations in a Canadian Indian population.

The living conditions of many aboriginal communities in Canada may place their residents at risk for H. pylori infection. Our aims were to determine: (1) the seroprevalence of H. pylori in a traditional Indian community, (2) the clinical relevance of H. pylori infection in this population, and (3) if H. pylori could be identified by polymerase chain reaction from the local water. A demographic questionnaire was administered, and blood was collected from subjects in an Indian community in northwestern Manitoba. The serum was analyzed by ELISA for IgG to H. pylori and to CagA. ABO and Lewis antigens were tested. Age-adjusted incidence of gastric cancer and of hospitalizations associated with diagnoses of peptic ulcer were determined for the Indian and non-Indian Manitoba population in the years 1989-1993. Nested PCR was performed on lake water using H. pylori-specific primers and the amplicons probed with an internal Dig-labeled probe. Three hundred six (59%) of approximately 518 individuals who were resident in the community at the time of the study were enrolled. The ELISA for H. pylori was positive in 291 (95%). There was no association between H. pylori seropositivity and age, sex, gastrointestinal complaints, medications, housing characteristics, and ABO or Lewis antigen status. CagA was positive in 84.5% of infected subjects. The average annual age-adjusted incidence of hospitalizations associated with diagnoses of peptic ulcer disease in Manitoba was higher for treaty-status Indians (394.3/100,000) than for non-Indians (203.8/100,000), but gastric cancer rates were similar (11.2/100,000 vs 11.6/100,000). No H. pylori DNA was detected in the lake water. In conclusion, the seroprevalence of CagA-positive H. pylori is high in this representative Manitoban Indian community. This may be associated with an increased risk for peptic ulcer disease but is not associated with an increased risk for gastric cancer.

Adolescent↗

The use of GAFchromic film to determine the absolute activity of beta emitters.

A method of using GAFchromic film to determine the absolute activity of beta emitters by immersing the film in a bath of activity is described. This includes calculations of the effect of part of the radioactive solution being displaced by the film that is performing the measurement. Calculations have been performed for 90Y, 32P and 188Re. It is shown that for the film used in this study, this effect will cause a correction of the order of 15-20% for the three radionuclides studied. The results of the GAFchromic film measurement are compared with results obtained from liquid scintillation counting and from a commercial dose calibrator. It is shown that for 32P all methods were in reasonable agreement, but for 188Re, although the GAFchromic film and the liquid scintillation counting methods give similar results, the dose calibrator measurement differed by more than 20%. The GAFchromic film was also used to perform a direct measurement of the radiation dose at a distance of 0.5 mm from the surface of a cylindrical source of 188Re activity. This gave good agreement with the value of the dose predicted from theoretical calculations.

Beta Particles↗

Helicobacter pylori in the Canadian arctic: seroprevalence and detection in community water samples.

OBJECTIVE: Many North American arctic communities are characterized by risk markers associated with Helicobacter pylori (H. pylori) infection, including overcrowded housing and inadequate water supply and sanitation systems. Our aim was to determine the seroprevalence of H. pylori infection in two traditional Inuit communities in the central Canadian arctic and to test for the presence of H. pylori, by polymerase chain reaction (PCR), in local water supplies. METHODS: Samples of venous whole blood from adults and capillary blood from children were collected and analyzed by enzyme immunoassay and Helisal Rapid Test, respectively, for IgG antibody to H. pylori. Antibodies to CagA were detected by enzyme immunoassay, and ABO and Lewis antigens were also determined. Demographic and clinical information were collected by questionnaire. Water samples from each community were tested for H. pylori by PCR. RESULTS: One hundred-thirty (50.8%) of 256 subjects from the two communities were positive for H. pylori IgG antibodies. Seropositive subjects were more likely to be male, compared with seronegative individuals (p = 0.01). Antibody status did not differ with respect to age, community, alcohol or cigarette use, number of persons per household, gastrointestinal complaints or previous investigations, medications, or presence of blood group O, Lewis a-b+. CagA antibodies were detected in 78 (61.9%) of 126 H. pylori-seropositive subjects tested; however, 41 (35.3%) of 116 H. pylori-seronegative subjects were also CagA positive. Water samples taken from the water delivery truck in Chesterfield Inlet and two lakes near Repulse Bay were positive for H. pylori. CONCLUSION: The seroprevalence of H. pylori in the study group was higher than rates in southern Canadian populations, but lower than the seroprevalence previously documented in a Canadian subarctic Indian (First Nations) community. The detection of H. pylori in local water supplies may indicate a natural reservoir for the organism or possible contamination from human sewage.

ABO Blood-Group System↗

Heart Link.

Explore the source record for details and available documents.

Child↗

Extradural analgesia and ichthyosis.

Extradural analgesia is well established for relief of pain but in certain cases unusual difficulties may be encountered. We report our experiences of a patient with congenital ichthyosis who required extradural analgesia for the relief of pain in labour.

Adult↗

Radioimmunoassay of O6-methyldeoxyguanosine in DNA of cells alkylated in vitro and in vivo.

Mouse monoclonal and rabbit polyclonal antibodies have been prepared against O6-methylguanosine complexed with bovine serum albumin. In radioimmunoassay 50% inhibition of binding of [3H]O6-methyldeoxyguanosine (O6-MedG) was obtained with 0.3 pmol or 0.16 pmol unlabelled O6-MedG using monoclonal or polyclonal antibodies having affinity constants of 3.0 X 10(9) and 5.9 X 10(9) I mol-1 respectively. Cross-reactivity with normal nucleosides and other adducts was determined. Sensitivity and reproducibility were improved by chromatographic separation using an Aminex A6 column eluted with 10 mM NH4HCO3 buffer which allowed quantitation of one molecule O6-MedG per 10(7) molecules dG in 2 mg calf thymine DNA. Values for O6-MedG from 14 samples of rat liver and kidney DNA analysed by the method described and by radiochromatography on Sephadex G10 were almost identical (correlation coefficient, 0.98). A modified procedure for the purification of 5-25 micrograms DNA from 1-5 X 10(6) fibroblasts applied to polycarbonate filters was used in providing further validation of the RIA system by measuring the persistence of O6-MedG in cell lines of known repair capacity.

Alkylation↗

Assessment of lead intakes and dose-response for a population in Ayr exposed to a plumbosolvent water supply.

1 Dietary lead intakes, blood lead concentrations and water lead concentrations were measured and their relationships investigated for 31 adults and 11 infants living in dwellings in Ayr with lead plumbing. 2 For adults, some lead intakes were found to be higher than the provisional tolerable weekly intake for lead, and for infants most of the intakes were high. 3 A cube root relationship fitted the data on blood lead versus water lead better than a linear relationship. Similarly, blood lead varied with the cube root of weekly dietary lead intake. 4 These cube root equations provided a means of estimating the impact on blood lead concentrations of exposure to lead from food and water. If cube root relationships correctly describe the association between these parameters, then the curve fitted to the results for adults indicates that the contribution to the blood lead concentrations from sources other than the diet and water was relatively small.

Adult↗