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In this case report we present a 49-year-old male who was seen in the emergency department after collapsing due to anaphylactic shock, with ECG findings suggesting myocardial ischaemia. We linked both diagnoses to Kounis syndrome, which describes an acute coronary syndrome due to an allergic event. His circulatory collapse was explained by exercise-induced anaphylaxis.

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Perturbed physics experiments are among the most comprehensive ways to address uncertainty in climate change forecasts. In these experiments, parameters and parametrizations in atmosphere-ocean general circulation models are perturbed across ranges of uncertainty, and results are compared with observations. In this paper, we describe the largest perturbed physics climate experiment conducted to date, the British Broadcasting Corporation (BBC) climate change experiment, in which the physics of the atmosphere and ocean are changed, and run in conjunction with a forcing ensemble designed to represent uncertainty in past and future forcings, under the A1B Special Report on Emissions Scenarios (SRES) climate change scenario.

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OBJECTIVES: The purpose of this study was to show that the chronotropic potential of the well trained heart transplant recipient (HTR) does not limit exercise capacity. BACKGROUND: Chronotropic incompetence is considered to be the main limiting factor of the functional capacity of heart transplant recipients. However, no systematic study had been published on patients who had spontaneously undergone heavy endurance training for several years. METHODS: Heart rate (HR) and respiratory gas exchanges (VO2, VCO2, VE) were measured in 14 trained HTRs (T-HTRs) during exercise tests on a bicycle, on a treadmill and by Holter electrocardiography during a race. RESULTS: Peak values observed in T-HTRs during the treadmill test were higher than those reached during the bicycle test (VO2peak: 39.8+/-6.9 vs. 32.5+/-7.8 ml x kg(-1) x min(-1), p < 0.001; HRpeak: 169+/-14 vs. 159+/-16 bpm, p < 0.01). During treadmill exercise VO2peak and HRpeak values observed were very close to the mean predicted VO2pmax and HRpmax. The maximum heart rate during the race (HRrace) was greater than HRpeak values during the treadmill test (179+/-14 vs 169+/-14 bpm, p < 0.01) and slightly above the mean predicted values (HRrace/HRpmax X 100 = 101+/-10%). The treadmill exercise test yields more reliable data than does the bicycle test. CONCLUSIONS: Extensive endurance training enables heart transplant recipients to reach physical fitness levels similar to those of normal sedentary subjects; heart rate does not limit their exercise capacity.

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The most common manifestations of Lyme disease are neurologic and rheumatologic, but ophthalmologic lesions can also occur and may even be dominant. The authors describe a case of bilateral optic neuropathy associated with Lyme borreliosis that quickly led to near-total blindness. In addition to a loss in visual acuity and field bilateral papillary edema was documented by angiofluorography. A spectacular improvement was obtained under combined antimicrobial therapy using doxycycline and corticosteroid therapy. The patient rapidly recovered full vision. These observations are discussed within the context of Lyme disease with a review of other relevant ophthalmologic complications. The importance of careful interpretation of serology is emphasized.

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Harada's disease is a uveo-meningitis syndrome characterized by meningo-encephalic manifestations preceded by bilateral posterior uveal lesions. The etiology of Harada's disease is still unclear but it probably involves an auto-immune reaction to melanocytes. This mechanism would account for the high incidence of Harada's disease in dark-skinned patients. This report describes a case of Harada's disease that occurred in a 28-year-old woman from North Africa. Ophthalmologic manifestations were typical with regard to clinical features and course involving bilateral papillary edema followed by exsudative detachment of the retina and diffuse cicatricial epitheliopathy of the posterior poles. However neurologic signs were mild, the main finding being atypical headache, and this particularity delayed diagnosis. Limited cerebral involvement that did not coincide with ocular lesions explains the fact that a thorough search for posterior uveal involvement with the aforesaid features was necessary. Although it occurs mainly in dark-skinned Asians, Harada's disease deserves the attention of physicians practicing in tropical areas.

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The CAGE/GEM(TM) software toolkit for genetic engineering is briefly described. The system functionally uses color graphics and is menu driven. It integrates genetics and features information ("Overlays") with information based on sequence analysis ("Representations"). The system is structured around CAD (Computer Aided Design) principles. The CAGE (Computer Aided Genetic Engineering) aspects of the software are emphasized and illustrated by a simulated cloning of the hepatitis B core antigen gene into the BAMHI site of plasmid pBR322.

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The pharmacokinetic properties of propranolol and atenolol were evaluated both in 9 patients with cirrhosis and in 12 healthy subjects. The hemodynamic effects of the drugs were evaluated separately in the cirrhotic patients. Propranolol and atenolol significantly decreased wedged hepatic venous pressure and cardiac output in cirrhotic patients. Propranolol Cmax, tmax and AUC were significantly increased and plasma half-life was significantly prolonged in cirrhotic patients. In contrast, the corresponding pharmacokinetic values of atenolol were not significantly different in cirrhotic patients and in healthy subjects.

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A series of 80 patients underwent continuous electrocardiography by Holter monitoring (ECG-H) for 24 hours to detect myocardial ischaemia. Fifty five patients were not on anti anginal therapy. The results of ECG-H were compared with those of exercise electrocardiography (ECG-E) (33 cases) and coronary angiography (50 cases). The ECG-H was positive in 31 of 43 patients (72%) with clinical (5 patients) or angiographic (38 patients) signs of ischaemic heart disease. The ECG-H was negative in 11 out of 12 patients (92%) with normal coronary; angiography. The sensitivity and specificity of ECG-H (57% and 92%) were inferior to those of ECG-E (75% and 100%) in the 33 untreated patients undergoing all three investigations. Twenty five recordings were compared with the ECG-E to assess anti anginal therapy. In asymptomatic patients ECG-H showed pathological ST depression in 10 cases, the ECG-E being positive in 1 7 cases. Anginal chest pain was induced on ECG-E in 5 out of 7 cases with a positive ECG-E and negative ECG-H. The lower sensitivity of the ECG-H compared to the ECG-E is related to several factors: 1) the sensitivity of the ECG-E increases with the number of exploratory electrodes; 2) reduced levels of physical activity decrease the sensitivity; in false negative cases the heart rate on ECG-H was only 74 +/- 7% of that corresponding to the threshold of positivity of the ECG-E, compared to 97 +/- 16% of the threshold heart rate in true positives (p less than 0,001); 3) the sensitivity of the ECG-H and ECG-E depends on the severity and distribution of the coronary lesions; false negative results were commoner in single vessel disease (57%) than in double or triple vessel disease (24%) (p less than 0,01). Anginal pain during the test increased the sensitivity to 92%. The specificity of the ECG-H is partially dependent on the recognition of positional variations of the ST segment. These were observed in 10% of cases but were generally easy to distinguish by their beat-to-beat appearances. The satisfactory specificity of the ECG-H in this study is also related to the high incidence of coronary artery disease in the population under study (80%). The predictive value of a positive test (Bayes theorem) was 97%, but that of a negative test was only 41%.

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Sixty-five patients, convalescent from a first myocardial infarction (anterior in 24 cases; inferior in 41 cases), underwent an effort electrocardiogram on a treadmill and coronary arteriography. In the anterior infarcts, coronary arteriography showed single vessel disease (anterior descending artery) in 54% of cases and double or triple vessel disease in the others. The effort test was positive in only 25% of patients with an anterior infarct. The presence of stenotic lesions of the circumflex artery and/or right coronary artery was unsuspected in 63% of patients. In the inferior infarcts, there was a significant stenosis of the anterior descending artery in 51% of the cases. The effort test was positive in 54% of patients and in 77% of those the anterior descending artery showed a significant stenosis. The appearance (or increase) of ST elevation greater than or equal to 1 mm in the leads facing the infarcted zone was an indication of more severe deterioration in left ventricular function as shown by a more marked reduction in ejection fraction and a more extensive akinetic region. The co-existence of ST elevation in the leads facing the infarcted zone and of ST depression greater than or equal to 1 mm in the reciprocal leads always indicated that another major vessel was involved, but this was only found in 25% of cases in this series.

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Eighty patients with continued or repeated episodes of chest pain at rest and transitory ischemic electrocardiographic (ECG) changes were classified as having unstable angina pectoris. Following 10 days of intensive medical therapy, including beta blockade, all unerwent coronary arteriography. Medical treatment completely relieved the chest pain in 43 patients (Group I, 54 percent). In 37 patients (Group II, 46 percent) angina recurred within a week of admission (12 patients) or later (25 patients). Seventeen patients were not operated upon (nine were inoperable, four refused operation, and in four operation was not recommended). Sixty-three underwent saphenous vein bypass grafting either following a month of medical therapy (Group I) or within 24 to 48 hours of recurrent angina (Group II). The over-all operative mortality rate was 1.6 percent (1 patient) and the incidence of peroperative infarction was 11 percent. Of the 62 operative survivors, 71 percent were asymptomatic (mean follow-up period 22 months). The incidence of late operative myocardial infarction was 5 percent. Of 44 operative survivors tested by treadmill ECG, 66 percent had a negative response. Thirteen patients underwent postoperative angiographic evaluation (mean, 19.5 months). The over-all patency rate was 84 percent, and in 92 percent of patients at least one graft was patent. Thus, after stabilization by medical treatment, bypass operation could be performed with a low operative mortality rate and the long-term results compare favorably with those achieved with chronic stable angina.

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