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61.
D Scheifele S Halperin L Pelletier J Talbot M Lovgren W Vaudry T Jadavji B Law N Macdonald R Gold E Wang E Mills M Lebel P Déry R Morris 《Journal canadien des maladies infectieuses》2001,12(4):241-246
OBJECTIVE: To determine, over time, the rate and serotypes of pneumococci with reduced penicillin susceptibility obtained from children with invasive infection. DESIGN: Active, hospital-based, multicentre surveillance spanning from 1991 to 1998. SETTING: Eleven Canadian tertiary care paediatric facilities located from coast to coast. POPULATION STUDIED: 1847 children with invasive pneumococcal infection whose isolates (from a normally sterile site) were available for serotyping and standardized testing for penicillin susceptibility at the National Centre for Streptococcus. MAIN RESULTS: The prevalence of reduced penicillin susceptibility increased from 2.5% of 197 cases in 1991 to 13.0% of 276 cases in 1998. In the latter year, 8.7% of isolates had intermediate level resistance, and 4.3% had high level resistance. Since they were first detected in 1992, strains with high level resistance have been encountered only sporadically at most centres, but by 1998, all centres but two had encountered examples. Of 40 isolates with high level resistance and 101 isolates with intermediate level resistance, serotypes matched those included in new seven-valent conjugate vaccines for children in 97.5% and 79.2% of cases, respectively. CONCLUSIONS: Pneumococci with reduced susceptibility to penicillin are increasing in frequency across Canada among children with invasive infection. The Immunization Monitoring Program, Active data indicate that new conjugate vaccines could help to curb infections due to pneumococci with reduced susceptibility to penicillin but are unlikely to control completely the problem of antibiotic resistance. 相似文献
62.
In two previous studies, we observed that recombinant human interleukin- 3 (IL-3) induced an increase in marrow burst-forming unit-erythroid- derived colonies in vitro in some patients with Diamond-Blackfan anemia (DBA). To determine whether a similar erythropoietic response could be induced in vivo, we treated 13 patients with DBA (aged 4 to 19 years) with two preparations of IL-3. All patients had absent absolute reticulocyte counts and markedly reduced to absent recognizable bone marrow erythroid elements; patients with circulating reticulocytes in the previous 12 months were excluded from study. All patients except 1 had failed steroid therapy and had been transfusion-dependent since infancy; 1 patient was maintained on high-dose prednisone at the time of enrollment. On the first arm of the study, IL-3 (Immunex Corp, Seattle, WA) was administered subcutaneously using a dose escalation regimen of 125 to 500 micrograms/m2/day in divided dosage at 12-hour intervals, coadministered with 1.5 mg/kg/d of oral ferrous sulphate. Of the 13 patients that entered the trial, 4 stopped prematurely because of adverse side effects. In the other 9 evaluable cases, reticulocytes increased transiently in 1 patient from 0 to 65 x 10(9)/L after 35 days of IL-3 therapy at 250 micrograms/m2, but transfusion dependency persisted. One transient peak in absolute reticulocyte count was noted in 6 other patients, but no erythroid response was observed after completion of a full course of IL-3. Oral prednisone at 0.5 mg/kg/d was then coadministered with IL-3 at 500 micrograms/m2 to 5 of the patients without effect, and treatment was stopped. In 2 patients, a second preparation of IL-3 (Sandoz Canada Inc, Dorval, Quebec, Canada) was initiated in a dose escalation regimen of 2.5 to 10 micrograms/kg and was coadministered with ferrous sulphate. No erythroid response was observed in either patient, and in one of the two, alternate-day subcutaneous recombinant erythropoietin at 300 U/kg was administered for 3 weeks in combination with daily IL-3 at 10 micrograms/kg, but no increased erythropoiesis was seen. Significant increases in white blood cell and eosinophil counts during administration of both preparations of IL-3 were observed in all patients. These data show that the response of DBA patients to IL-3 in vivo is heterogeneous and cannot be predicted from in vitro studies. The absence of a corrective effect of IL-3 in these patients with DBA indicates that a deficiency of the cytokine is not central in the pathogenesis of the disorder. 相似文献
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Jean-Sébastien Pelletier Christopher DeGara Geoff Porter Sunita Ghosh Dan Schiller 《Canadian journal of surgery》2013,56(4):E51-E58
Introduction
Previous studies, including research published more than 10 years ago in Northern Alberta, have demonstrated improved outcomes with increased surgical volume and subspecialisation in the treatment of rectal cancer. We sought to examine contemporary rectal cancer care in the same region to determine whether practice patterns have changed and whether outcomes have improved.Methods
We reviewed the charts of all patients with rectal adenocarcinoma diagnosed between 1998 and 2003 who had a potentially curative resection. The main outcomes examined were 5-year local recurrence (LR) and disease-specific survival (DSS). Surgeons were classified into 3 groups according to training and volume, and we compared outcome measures among them. We also compared our results to those of the previous study from our region.Results
We included 433 cases in the study. Subspecialty-trained colorectal surgeons performed 35% of all surgeries in our study compared to 16% in the previous study. The overall 5-year LR rate and DSS in our study were improved compared to the previous study. On multivariate analysis, the only factor associated with increased 5-year LR was presence of obstruction, and the factors associated with decreased 5-year DSS were high-volume noncolorectal surgeons, presence of obstruction and increased stage.Conclusion
Over the past 10 years, the long-term outcomes of treatment for rectal cancer have improved. We found that surgical subspecialization was associated with improved DSS but not LR. Increased surgical volume was not associated with LR or DSS. 相似文献68.
Z Khalpey MH Yacoub RT Smolenski 《Annals of the Royal College of Surgeons of England》2013,95(1):9-14
Introduction
Human donor organ shortages have led surgeons and scientists to explore the use of animals as alternative organ sources. Acute thrombovascular rejection (AVR) is the main hurdle in xenotransplantation. Disparities in nucleotide metabolism in the vessels of different species may contribute significantly to the microvascular component of AVR.Methods
We evaluated the extent of nucleotide metabolism mismatch in selected organs and endothelial cells of different mammals with particular focus on the changes in activity of ecto-5’-nucleotidase (E5’N) elicited by exposure of porcine hearts or endothelial cells to human blood (ex vivo) or human plasma (in vitro).Results
E5’N activity in the rat heart was significantly higher than in other species. We noted a significant difference (p<0.001) in E5’N activity between human and pig endothelial cell lines. Initial pig aortic endothelial E5’N activity decreased in vitro after a three-hour exposure to human and porcine plasma while remaining constant in controls. Ex vivo perfusion with fresh human blood for four hours resulted in a significant decrease of E5’N activity in both wild type and transgenic pig hearts overexpressing human decay accelerating factor (p<0.001).Conclusions
This study provides evidence that mismatches in basal mammalian metabolic pathways and humoral immunity interact in a xenogeneic environment. Understanding the role of nucleotide metabolism and signalling in xenotransplantation may identify new targets for genetic modifications and may lead to the development of new therapies extending graft survival. 相似文献69.
DC Bosanquet CN Jones N Gill P Jarvis MH Lewis 《Annals of the Royal College of Surgeons of England》2013,95(1):15-19
Introduction
Numerous strategies are employed routinely in an effort to lower rates of surgical site infections (SSIs). A laminar flow theatre environment is generally used during orthopaedic surgery to reduce rates of SSIs. Its role in vascular surgery, especially when arterial bypass grafts are used, is unknown.Methods
A retrospective review of a prospectively maintained database was undertaken for all vascular procedures performed by a single consultant over a one-year period. Cases were performed, via random allocation, in either a laminar or non-laminar flow theatre environment. Demographic data, operative data and evidence of postoperative SSIs were noted. A separate subgroup analysis was undertaken for patients requiring an arterial bypass graft. Univariate and multivariate logistical regression was undertaken to identify significant factors associated with SSIs.Results
Overall, 170 procedures were analysed. Presence of a groin incision, insertion of an arterial graft and a non-laminar flow theatre were shown to be predictive of SSIs in this cohort. In the subgroup receiving arterial grafts, only a non-laminar flow theatre environment was shown to be predictive of an SSI.Conclusions
This study suggests that laminar flow may reduce incidences of SSI, especially in the subgroup of patients receiving arterial grafts. 相似文献70.
AbstractThree cases of Friedreich’s ataxia were submitted to diverse neuroradiological procedures in order to determine the extent of atrophic processes in the central nervous system. All patients underwent computerized-tomography scan, Magnetic Resonance Imaging, and HMPA-single Photon emission computerized tomography studies, focusing in cerebellar lobes. A slight atrophy was observed in the vermis and the cerebellar lobes with CT scan and MRI. In contrast a significant decrease in cerebellar blood flow was shown by TC-HMPAE SPECT study. The significance of these findings in understanding physiopathological mechanisms in Friedreich’s ataxia is discussed. [Neurol Res 1994; 16: 342-344] 相似文献