Recurrent ophthalmoplegia in childhood: diagnostic and etiologic considerations

We present two patients with recurrent painful ophthalmoplegia starting in early childhood. Clinically, both patients fulfilled the criteria for ophthalmoplegic migraine. In one case, magnetic resonance investigations were performed following the second attack, between the third and fourth and during the fourth attack. The left third cranial nerve was significantly thickened in its course from the brainstem through the prepontine cistern to the cavernous sinus during the attacks and moderately thickened between the attacks. In the second case, magnetic resonance imaging was performed during the 14th attack, when the oculomotor nerve dysfunction was almost permanent, and the imaging demonstrated a swollen oculomotor nerve. Whether these findings are pathognomonic of ophthalmoplegic migraine awaits further reports using magnetic resonance imaging in infants showing recurrent painful ophthalmoplegia of early onset.     

What is a safe waiting time for coronary artery bypass surgery?

To determine the factors that influenced doctors' prioritization and decisions on safe waiting time for coronary artery bypass surgery, 50 'paper patients', based on a random sample of cases who actually had surgery, were assessed by 33 clinicians. We used linear regression models to reflect the impact of clinical and non-clinical 'cues' on safe waiting time and priority decisions. The benefits of surgery tended to be over-estimated. For example, the average perceived gain in life expectancy for patients with left main-stem disease was 6.74 years. However, models incorporating only the perceptions of benefit as independent variables (i.e. the anticipated symptom reduction, MI risk reduction and life expectancy extension), had only modest explanatory power (mean R2 was 0.55 for safe waiting time, and 0.56 for priority decisions). Models which incorporated perceptions of benefit and the cases' clinical and non-clinical characteristics had generally much higher explanatory power (mean R2, 0.83 and 0.86, respectively). Lifestyle and demographic variables had much less impact on the doctors' judgements than the major clinical cues of angina severity and left main-stem stenosis. Demographic and lifestyle cues had different impacts on safe waiting time and priority for about 25% of doctors.      

Increased Risk of Ventricular Fibrillation Associated with Temporary Pacemaker Use During Coronary Arteriography

Each injection of angiographic contrast dye during coronary arteriography represents a "natural experiment" in which the human ventricular fibrillation threshold is transiently reduced. Few factors, however, have been identified which favor the actual occurrence of ventricular fibrillation in this setting. Of 3906 consecutive patients undergoing selective coronary arteriography with sodium meglumine diatrizoate, 66(1.7 percent) experienced dye-induced ventricular fibrillation, from which all were successfully defibrillated. Analysis of these cases revealed, unexpectedly, that patients in whom temporary right ventricular pacemakers were employed had an incidence of ventricular fibrillation nearly six times that found in the entire group undergoing arteriography (10 percent vs. 1.7 percent, respectively; P<.001). Those individuals receiving pacemakers were distinguished from other studied patients only by a higher prevalence of conduction abnormalities. Although there is normally a low probability that mechanical stimulation by a pacing catheter can induce ventricular fibrillation, it is postulated that such an occurrence may be more likely after ventricular vulnerability has been increased by contrast dye.     

The stated and tacit impact of demographic and lifestyle factors on prioritization decisions for cardiac surgery

In a clinical judgement analysis, we used linear regression models to reflect the impact of clinical and non-clinical cues on priority decisions, by comparing the stated prioritization policies of 30 clinicians with their actual policies as revealed by an appraisal of 50 'paper patients'. Correspondence was modest for some cues, e.g. 25 doctors said they accounted for age, but age only had a significant bearing in the derived decision models of two doctors. Correspondence between the derived and expressed weights was greatest for clinical angina grade and the presence of left main stem stenosis. Correlation between the rank order of importance between the two models was poor for most of the cues, and statistically significant only for smoking. However, stated policies made it appear that lifestyle factors such as smoking habit would influence prioritization decisions for most clinicians but policies derived from actual prioritization decisions seldom related to lifestyle or demographic variables. There were significant differences in the degree of correlation between the two models according to the experience of the clinician. However, correspondence was not significantly better for doctors with cardiological training than those without. The overall contribution of demographic and lifestyle factors to decision making appears to be small, suggesting that they should be omitted from prioritization guidelines.      

Comparison of cell-surface TFPIα and β

BACKGROUND: Tissue factor pathway inhibitor (TFPI) is mainly produced by endothelial cells and alternative mRNA splicing generates two forms, TFPIalpha and TFPIbeta. A portion of expressed TFPI remains associated with the cell surface through both direct (TFPIbeta) and indirect (TFPIalpha) glycosylphosphatidyl-inositol (GPT)-mediated anchorage. OBJECTIVE: Compare the structure and properties of TFPIalpha and TFPIbeta. METHODS: TFPIalpha and TFPIbeta, with protein molecular masses of 36 and 28 kDa, respectively, migrate similarly (46 kDa) on SDS-PAGE. Experiments using specific glycosidases were carried out to determine the different glycosylation pattern of the two forms. ECV304 cells, a cell line with some endothelial properties, were stimulated with IL-lbeta, LPS, and TNFalpha for up to 24 hrs and mRNA levels and protein synthesis were determined. Stable clones of ECV304 cells that express reduced levels of TFPIalpha, TFPIbeta or both were produced using a plasmid-based small-interfering RNA technique. Surface TFPI activity was determined by a two-stage chromogenic assay based on the ability of each form to inhibit FXa activation by FVIIa on cells with comparable amount of tissue factor (TF). RESULTS AND CONCLUSIONS: The deglycosylation studies show that the difference in molecular masses is due to a greater degree of sialylation in O-linked carbohydrate in TFPIbeta. The mRNA and protein levels of neither form of TFPI were affected by stimulation of cells with inflammatory stimuli. Although TFPIalpha comprises 80% of the surface-TFPI, TFPIbeta was responsible for the bulk of the cellular FVIIa/TF inhibitory activity, suggesting a potential alternative role for cell surface TFPIalpha.     

SQUAMOUS CARCINOMA OF THE RECTUM

SUMMARY A case of squamous carcinoma of the rectum in a 50-year-old woman is reported, which was treated by excisional surgery and then radiotherapy. The patient is alive and well, with no evidence of tumour recurrence 6 years later. The aetiology and treatment of this uncommon tumour is discussed.     

Heart Block and Idiopathic Pulmonary Hemosiderosis

A young woman with idiopathic pulmonary hemosiderosis (IPH) and advanced heart block below the atrioventricular node requiring pacemaker therapy is discussed. Thirteen years after the onset of IPH she is free of pulmonary symptoms despite having never received steroid or antimetabolite therapy.