Most axons in the central nervous system (CNS) are surrounded by a multilayered myelin sheath that promotes fast, saltatory conduction of electrical impulses. By insulating the axon, myelin also shields the axoplasm from the extracellular milieu. In the CNS, oligodendrocytes provide support for the long-term maintenance of myelinated axons, independent of the myelin sheath.
View Article and Find Full Text PDFAim: To determine whether mortality following percutaneous coronary intervention vs. coronary bypass grafting varies according to whether or not patients have diabetes.
Methods: We used the Scottish Coronary Revascularization Register to identify all patients undergoing revascularization in Scottish NHS hospitals since 1997.
Objective: To determine current outcomes of percutaneous transluminal coronary angioplasty (PTCA) and coronary artery bypass grafting (CABG).
Design: The Scottish coronary revascularisation register provided prospectively collected data on case mix and in-hospital complications for all revascularisation procedures between April 1997 and March 1999 (4775 PTCA; 5115 CABG). Linkage to routine hospital discharge and death data provided follow up information on survival and repeat revascularisation.
Objective: To compare the national samples of patients who underwent isolated coronary artery bypass grafting (CABG) during the European System for Cardiac Operative Risk Evaluation (EuroSCORE) trial in order to evaluate national differences in epidemiology, patient risk profile and surgical methods.
Methods: From September to November 1995, 11731 patients had CABG in the six largest contributing nations to the EuroSCORE project: Germany, UK, Spain, Finland, France and Italy. The Chi-square and Kruskal-Wallis tests were applied to obtain an international comparison of patient general status, including pre-operative risk factors, cardiac status, critical pre-operative states, rare conditions, urgency of surgery, angina status, coronary lesions, procedures and EuroSCORE risk assessment.
Objective: To assess risk factors for mortality in cardiac surgical adult patients as part of a study to develop a European System for Cardiac Operative Risk Evaluation (EuroSCORE).
Methods: From September to November 1995, information on risk factors and mortality was collected for 19030 consecutive adult patients undergoing cardiac surgery under cardiopulmonary bypass in 128 surgical centres in eight European states. Data were collected for 68 preoperative and 29 operative risk factors proven or believed to influence hospital mortality.
Cineradiography, using higher kVp and two or more specified profiles for each outlet strut leg, was used to evaluate Björk-Shiley convexo-concave (C/C) heart valves with epidemiologically defined > 0.1% per year estimated fracture rates. Among 828 mitral valves, eight radiographs were assessed as definite single leg separations (SLS) and 23 were read as probable SLS.
View Article and Find Full Text PDFJ Thorac Cardiovasc Surg
March 1996
We conducted a prospective, randomized trial of three methods of rewarming patients after hypothermic cardiopulmonary bypass. Patients underwent either coronary artery bypass grafting or first-time valve replacement and were cooled to 32 degrees C during bypass. No significant differences existed among the groups as regards operative or preoperative parameters including hemodynamics and blood use.
View Article and Find Full Text PDFDoppler ultrasound detection of abnormally high-pitched signals within the arterial waveform offers a new method for diagnosis, and potentially for prediction, of embolic complications in at-risk patients. The nature of Doppler "microembolic" signals is of particular interest in patients with prosthetic heart valves, where a high prevalence of these signals is observed. Monitoring the middle cerebral artery with 2-MHz transcranial Doppler ultrasound (TC-2000, Nicolet Biomedical; Warwick, UK), we looked for microemboli signals in 150 patients (95 women and 55 men), and found 1 or more signals during a 30-min recording in 89% of 70 patients with Bjork-Shiley valves (principally monostrut), 54% of 50 patients with Medtronic-Hall valves, and 50% of 30 patients with Carpentier-Edwards valves (p < 0.
View Article and Find Full Text PDFEur J Cardiothorac Surg
November 1996
Transcranial Doppler ultrasound has revealed the existence of cerebrovascular microemboli in asymptomatic patients with prosthetic heart valves. We investigated the relation between the presence and number of emboli signals and valve type. Patients with six types of prosthetic valves (Björk-Shiley monostrut, Medtronic-Hall, Carbomedics, ATS, Carpentier-Edwards standard, Carpentier-Edwards supraannular) were examined using transcranial Doppler ultrasound in two centers.
View Article and Find Full Text PDFThis study was undertaken in 64 patients, 50 with mechanical and 14 with porcine prosthetic valves, to evaluate the incidence of intracranial emboli and their distribution in the basal cerebral arteries. The patients were studied using transcranial Doppler (EME TC2-64B, Uberlingen, Germany), with a monitoring time of two minutes over each of the internal carotid arteries, middle and anterior cerebral arteries, vertebral arteries and the basilar artery. Sixty-three of the 64 patients were stabilized on warfarin at the time of the study.
View Article and Find Full Text PDFPatients undergoing prosthetic valve insertion and coronary artery bypass surgery were examined with transcranial Doppler ultrasound, recently shown to be capable of detecting continuing subclinical emboli in patients with embolic sources. In 30 patients examined at least 1 year after valve surgery, and in whom warfarinisation was stable within defined limits, 20 of 24 patients (83%) with mechanical valves and 3 of 6 patients (50%) with porcine valves had embolic signals. In a serial preoperative and postoperative study in a further 30 patients, of whom 29 had native or bioprosthetic valves, only the one patient with a previous mechanical mitral valve prosthesis had embolic signals preoperatively.
View Article and Find Full Text PDFThe concentrations of testosterone, free testosterone index derived by two independent techniques (FTI1, FTI2), dehydroepiandrosterone sulphate (DHAS), androstenedione (AND), luteinizing hormone (LH), follicle stimulating hormone (FSH), and sex hormone binding globulin (SHBG) were measured in 38 healthy male controls aged between 40 and 60 years (Group 1) and in 52 male patients with bronchial carcinoma of whom 28 were aged between 40 and 60 years (Group 2) and 24 were aged over 60 years (Group 3). Compared with Group 1, testosterone, FTI1, FTI2, and DHAS were significantly lower (P < 0.001), AND and LH were significantly higher (P < 0.
View Article and Find Full Text PDFTwo methods of quantifying oesophageal emptying for liquids have been used to assess the dysphagia of patients with systemic sclerosis: the oesophageal infusion scintiscan and the timed Gastrografin swallow. Upper gastrointestinal endoscopy and oesophageal manometry were also performed. Thirteen patients with oesophageal symptoms were studied.
View Article and Find Full Text PDFSerum testosterone concentrations were measured preoperatively in 39 men undergoing thoracotomy for histologically proved bronchial carcinoma, in 10 patients with pulmonary opacities that transpired to be non-malignant (benign group) and in 23 men were undergoing minor elective surgical procedures (control group). Thirteen of the 39 patients with known bronchial carcinoma were considered to have had curative surgery and 26 a palliative procedure when operative and pathological findings were taken into consideration. Low serum testosterone concentrations (less than 12 nmol/l) were detected in four patients in the curative group, in 22 in the palliative group (chi 2 test: p less than 0.
View Article and Find Full Text PDFIn a double blind, prospective, randomised study of 100 patients undergoing elective cardiac surgery, a significant (p less than 0.01) reduction in wound colonisation, defined as positive culture of any wound discharge irrespective of wound appearance, occurred in those receiving preincisional presternal antibiotic infiltration (2%) as compared to a control group who received a similar volume of normal saline by the same route (24%). Both groups received, in addition, the same conventional intravenous regimen of broad spectrum antibiotic.
View Article and Find Full Text PDFLung tumours of non small cell pathology were cultured by clonogenic assay in several media. Culture was successful in spleen conditioned medium, but only 57% grew and low plating efficiencies (PE) meant that only 23% of the original number produced significant drug results. Comparison of rat erythrocyte lysate (REL) medium with serum free defined medium (HITES) and HITES + 10% FBS demonstrated clear enhancement of PE in REL although growth was 100% successful in all these media.
View Article and Find Full Text PDFSixty-six patients with lung cancer underwent mediastinal staging with gallium scanning, CT scanning and mediastinal exploration at mediastinoscopy and/or thoracotomy. Histological findings at time of mediastinal exploration were correlated with the results of the non-invasive staging scans. Gallium scanning had an accuracy of 78.
View Article and Find Full Text PDFA prospective double blind, randomised study was performed in 100 patients undergoing major elective thoracic surgery to assess a new method of prophylaxis of wound infection using one preincisional intraparietal infiltration of cefuroxime sodium along the line of proposed incision as the sole protection against wound infection. A significant (p less than 0.01) reduction in the incidence of wound infection occurred in the antibiotic treated group (2%) compared with the control group (20%), who received by the same route the same volume of saline only.
View Article and Find Full Text PDFFrom 1972 to 1981 40 patients have required urgent valve replacement for left-sided bacterial endocarditis. The aortic valve was replaced in 31 patients, the mitral valve in four, and both in five patients. Twenty-six patients (65.
View Article and Find Full Text PDFThe effects of prostacyclin (PGI2) on postoperative blood loss and on the deposits which are known to form on filters in the bypass circuit were studied in patients undergoing operations with cardioopulmonary bypass. In this double-blind, randomized study, PGI2 or a placebo solution was administered to 56 patients undergoing elective cardiac operations. At the end of cardipulmonary bypass, the arterial line filter was removed from the circuit and blood losses were accurately recorded.
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