Massive hemolysis and acute mitral insufficiency one year following mitral valve repair. Apropos of a case

The authors report a case of massive haemolytic anaemia with acute mitral valve regurgitation and left cardiac failure, which occurred one year after surgical reconstruction of the mitral valve for rupture of smaller leaflet chordae. Anaemia, mitral regurgitation and cardiac failure disappeared after mitral valve replacement, using a Carpentier Edwards No. 29 valve. Haemolytic anaemia following mitral valve reconstruction is exceptional. It seems to be due to the suture material lying in a turbulent regurgitation stream when mitral incompetence develops again.     

Thrombosis and thrombolysis in unstable angina

Pathophysiology of unstable angina involves spasm, plaque rupture, activation of platelets, and coagulation. The incidence and frequency of intracoronary thrombus formation are presently under active assessment in order to establish the potential benefit of thrombolytic therapy. A preliminary study was conducted in patients admitted in our coronary care unit for unstable angina with typical clinical and electrocardiographic criteria and with early coronary angiogram. After exclusion of 4 patients with left main coronary stenosis or contraindications for thrombolysis, 16 patients received thrombolytic infusion and 14 underwent a second coronary angiogram. Seven patients had an intracoronary thrombus (6 nonocclusive, 1 occlusive) and at the second angiogram only 3 nonocclusive thrombi were modified (1 disappeared, 2 were reduced). Moreover, the quantitative Coronary Angiography Analysis System (CAAS) in the 11 cases suitable for analysis did not show any significant changes, especially in the Ambrose type IIB lesions. In-hospital clinical outcome was not influenced by thrombolytic therapy (5 ischemic recurrences, 1 fatal myocardial infarction, 4 emergency and 4 elective revascularization procedures). This short series is in agreement with the literature data. Only one third of patients with active unstable angina remains refractory to conventional therapy. The transient benefit of thrombolysis is limited to patients with demonstrated intracoronary thrombi. Clinical or angiographic improvement are not always in correlation and until now do not seem able to prevent short-term recurrences or the need for revascularization procedures.     

High amounts of circulating interleukin (IL)-6 in the form of monomeric immune complexes during anti-IL-6 therapy. Towards a new methodology for measuring overall cytokine production in human in vivo.

A patient with plasma cell leukemia was treated with anti-interleukin (IL)-6 monoclonal antibodies (mAb) for 2 months. Using chromatography on protein A-Sepharose, anti-murine-IgG-Sepharose, anti-IL-6-mAb-Sepharose and gel filtration at pH 2.3, we have demonstrated that the anti-IL-6 mAb, by preventing the binding of IL-6 to its cell membrane receptor and its renal elimination, has induced huge amounts of IL-6 to circulate in the form of monomeric immune complexes. By using this observation, we have developed a mathematical modelling that allows the determination of the overall daily production of IL-6 in this patient, which was in the range of 15 micrograms per day. Overall in vivo production of cytokines has never been evaluated in animals or in humans before.     

Activity in ventral and dorsal premotor cortex in response to predictable force-pulse perturbations in a precision grip task

This study compared the responses of ventral and dorsal premotor cortex (PMv and PMd) neurons to predictable force-pulse perturbations applied during a precision grip. Three monkeys were trained to grasp an unseen instrumented object between the thumb and index finger and to lift and hold it stationary within a position window for 2-2.5 s. The grip and load forces and the object displacement were measured on each trial. Single-unit activity was recorded from the hand regions in the PMv and PMd. In some conditions a predictable perturbation was applied to the object after 1,500 ms of static holding, whereas in other conditions different random combinations of perturbed and unperturbed trials were given. In the perturbed conditions, some were randomly and intermittently presented with a warning flash, whereas some were unsignaled. The activities of 198 cells were modulated during the task performance. Of these cells, 151 were located in the PMv, and 47 were located in the PMd. Although both PMv and PMd neurons had similar discharge patterns, more PMd neurons (84 vs. 43%) showed early pregrip activity. Forty of 106 PMv and 10/30 PMd cells responded to the perturbation with reflexlike triggered reactions. The latency of this response was always <100 ms with a mean of about 55 ms in both the PMv and the PMd. In contrast, 106 PMv and 30 PMd cells tested with the perturbations, only 9 and 10%, respectively, showed significant but nonspecific adaptations to the perturbation. The warning stimulus did not increase the occurrence of specific responses to the perturbation even though 21 of 42 cells related to the grip task also responded to moving visual stimuli. The responses were retinal and frequently involved limited portions of both foveal and peripheral visual fields. When tested with a 75 x 5.5-cm dark bar on a light background, these cells were sensitive to the direction of movement. In summary, the periarcuate premotor area activity to related to predictable force-pulse perturbations seems to reflect a general increase in excitability in contrast to a more specific anticipatory activity such as recorded in the cerebellum. In spite of the strong cerebello-thalamo-cortical projections, the results of the present study suggest that the cortical premotor areas are not involved in the elaboration of adaptive internal models of hand-object dynamics.     

Analysis of segmental kinetics of the left ventricle after intravenous administration of urokinase in the acute phase of myocardial infarction

From 1982 to 1984 included, 31 patients under 70 years of age were admitted during the first three hours of a primary myocardial infarction (MI) and are the subject of a randomized prospective study. 16 patients are treated with 5,000 U of heparin given in intravenous bolus, followed with 150,000 IU of urokinase (UK) in intravenous bolus, then 12,000 IU of UK/min for 90 min or a total dose of 1,230,000 IU. 15 patients are treated with heparin alone (intravenous bolus of 5,000 U). Repeated titrations of creatine phosphokinase (CPK) and the coagulation parameters are performed during the first 24 hours. A coronary angiography with ventriculography (RAO 30 degrees) is performed on the 1st day (D1) and the 3rd week (W3). Study of the left ventricular kinetics (LV) is carried out according to the Stanford method. At D1, the rate of coronary patency is 56 p cent (n = 9) in the UK (A) group and 53 p. cent (n = 8) in the control group B (heparin alone). The percentage of late re-thrombosis is 0 p. cent in group A and 12.5 p. cent in group B (heparin alone). 1 patient died in each group. The CPK peak is less high in case of coronary patency in group A than in case of thrombosis (1,444 +/- 413 vs 1,710 +/- 120 U -heparin alone) and occurs earlier (16 +/- 2 h vs 21 +/- 1 h). In group A a significant decrease of fibrinogen (p. 0.01) as well as plasminogen and alpha-2-antiplasmins (p less than 0.001), is noted. No severe haemorrhagic complications nor sustained rhythm disorders are noted.(ABSTRACT TRUNCATED AT 250 WORDS)     

Animals, public health and the example of cowpox

Public attitudes towards animals are often contradictory. In developed countries where the problem of food security has been solved to a large degree, public concern is concentrated on food safety and animal welfare, along with a debate on the social status of both domestic and wild animals. Zoonoses are often the focal point of these concerns. In developing countries (which often have the greatest biodiversity), wildlife constitutes an uncontrollable source of often unknown zoonoses. The authors attempt to analyse the link between animals and public health. Special attention is given to the example of cowpox, a disease which has been recognised as a zoonosis for more than two centuries but the epidemiology of which has recently been rediscovered.     

Surgical treatment of congenital aortic valve constriction with associated obstructive cardiomyopathy. Perioperative left intraventricular gradient treated with beta blockers. Apropos of a case

The authors report a case of congenital valvular aortic stenosis associated with echocardiographic and angiographic appearances of hypertrophic obstructive cardiomyopathy. After valvular replacement and partial myotomy a high intraventricular pressure gradient (125 mmHg) with low intra aortic pressure was recorded. High dose intravenous propranolol (25 mg in 2 hours) reduced this gradient to 50 mmHg allowing cardiopulmonary bypass to be discontinued. This clinical combination is associated with a risk of aggravation of the intra-ventricular obstructive phenomenon when the obstacle to left ventricular ejection is relieved: surgical myotomy was performed in similar, previously published cases. High doses betablocker therapy can be performed in similar, previously published cases. High dose betablocker therapy can be useful in this association and it may also be instituted when right intraventricular pressure gradient increase after relief of pulmonary valvular stenosis.     

Investigation into non-monosynaptic corticospinal excitation of macaque upper limb single motor units

There has been considerable recent debate as to relative importance, in the primate, of propriospinal transmission of corticospinal excitation to upper limb motoneurons. Previous studies in the anesthetized macaque monkey suggested that, compared with the cat, the transmission of such excitation via a system of C3-C4 propriospinal neurons may be relatively weak. However, it is possible that in the anesthetized preparation, propriospinal transmission of cortical inputs to motoneurons may be depressed. To address this issue, the current study investigated the responses of single motor units (SMUs) to corticospinal inputs in either awake (n = 1) or lightly sedated (n = 3) macaque monkeys. Recordings in the awake state were made during performance of a precision grip task. The responses of spontaneously discharging SMUs to electrical stimulation of the pyramidal tract (PT) via chronically implanted electrodes were examined for evidence of non-monosynaptic, presumed propriospinal, effects. Single PT stimuli (up to 250 microA; duration, 0.2 ms, 2 Hz) were delivered during steady discharge of the SMU (10-30 imp/s). SMUs were recorded from muscles acting on the thumb (adductor pollicis and abductor pollicis brevis, n = 18), wrist (extensor carpi radialis, n = 29) and elbow (biceps, n = 9). In all SMUs, the poststimulus time histograms to PT stimulation consisted of a single peak at a fixed latency and with a brief duration [0.74 +/- 0.25 (SD) ms, n = 56], consistent with the responses being mediated by monosynaptic action of cortico-motoneuronal (CM) impulses. Later peaks, indicating non-monosynaptic action, were not present even when the probability of the initial peak response was low and when there was no evidence for suppression of ongoing SMU activity following this peak (n = 20 SMUs). Even when repetitive (double-pulse) PT stimuli were used to facilitate transmission through oligosynaptic linkages, no later peaks were observed (16 SMUs). In some thumb muscle SMUs (n = 8), responses to PT stimulation were compared with those evoked by transcranial magnetic stimulation, using a figure-eight coil held over the motor cortex. Responses varied according the orientation of the coil: in the latero-medial position, single peak responses similar to those from the PT were obtained; their latencies confirmed direct excitation of CM cells, and there were no later peaks. In the posterio-anterior orientation, responses had longer latencies and consisted of two to three subpeaks. At least under the conditions that we have tested, the results provide no positive evidence for transmission of cortical excitation to upper limb motoneurons by non-monosynaptic pathways in the macaque monkey.