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Background: There is presently no cure for locomotor deficits after spinal cord injury (SCI). Very few therapies effectively target the brain due to poor understanding of the brain’s role post-SCI. Newly developed tissue clearing techniques have permitted unbiased three-dimensional circuit analysis, opening new opportunities for SCI-related brain interrogation. Methods: We established a novel brain interrogation pipeline by optimizing mouse brain clearing, imaging, and atlas registration. We leveraged a spontaneous recovery lateral hemisection model to analyze whole brain cell activity and connectivity with the lumbar cord using cFos immunolabelling and virus-mediated projection tracing. We identified a functionally and anatomically dynamic region correlating with recovery and interrogated its locomotor role with optogenetics. We assessed deep brain electrical stimulation (DBS) of this region in a more clinically relevant rat contusion SCI using an established bipedal robotic interface. Results: We unexpectedly uncovered the lateral hypothalamus (LH) to functionally and anatomically correlate with recovery. LHVglut2 optogenetic stimulation significantly augmented locomotor function. LH DBS in rats acutely robustly augmented bipedal locomotion post-SCI. Conclusions: This is the first demonstration of the LH’s role in locomotion post-SCI and is a novel DBS target that robustly augmented locomotor function, dependent on LH glutamatergic cells. LH DBS may be a promising intervention in humans.

The prevalence and severity of extracoronary atherosclerosis in 728 patients (572 men and 156 women; average age 59 years) referred for coronary angiography and who had a history of coronary disease for at least 2 years, were assessed by ultrasonography. This population was divided into 3 groups: Group I, 115 patients without lesions at coronary angiography: Group II, 76 patients with mild coronary stenosis ang Group III, 537 patients with at least one severe coronary artery stenosis, a group which included 294 cases of single vessel disease. The authors observed a strong correlation between the presence, severity and diffusion of the coronary artery disease and ultra sonographic signs of peripheral arterial disease: the frequency increased regularly from 45% in Group I to 88% in patients with triple vessel disease in Group III. About two thirds of patients in Group III had carotid or lower limb atherosclerosis and half of them had atherosclerosis or aneurysm of the abdominal aorta. Severe peripheral lesions were not common but all the aortic aneurysms were observed in Group III. Similarly, simultaneous disease in all three peripheral arterial territories ranged from 12% in Group I to 51% in Group III. The risk of finding peripheral arterial disease was increased in patients with coronary artery disease compared with normal subjects. For each peripheral localisation, the risk was two-fold in cases of mild coronary disease and three or four-fold in patients with triple vessel disease in whom the risk of finding at least one severe peripheral lesion was multiplied by ten. The authors conclude that the prevalence and severity of ultrasonographic peripheral atherosclerosis in documented coronary patients was closely related to the presence, severity and diffusion of the coronary lesions.

Detection of asymptomatic abdominal aortic aneurysm (AAAA) was studied in 780 patients whose coronary disease had been evolving for less than 2 years, who had undergone coronagraphy within the framework of the French ALAC Survey (Autres Localisations de l'Athérosclérose chez le Coronarien--other locations of atherosclerosis in coronary disease) and had an interpretable abdominal aortic echography. Clinical and echographic research detected 19 AAAA cases in 15 men and 4 women aged 53 to 77 years having at coronagraphy at least one stenosisor = 70% on one of the 3 coronary trunks oror = 50% on the commun trunk. Among the 577 coronary disease patients with at least one significant stenosis, the prevalence of AAAA was 3.3%. Seventeen aneurysms were missed at abdominal palpation. A subgroup of 458 patients aged 50 to 79 years had significant coronary stenosis without history of aortic surgery. There was no significant difference between the 19 AAAA cases and the 439 cases of coronary disease without aortic aneurysm, as regards risk factors, especially age, high blood pressure and tobacco consumption. On the other hand, the 19 AAAA cases had more diffused and more severe atherosclerotic lesions in the lower limbs and carotid arteries. Abdominal echography is essential for the detection of AAAA in patients with coronary disease.

The elderly population is particularly exposed to risk of venous thromboembolism because the risk of thrombosis increases with age but also because of the side effects of anticoagulant therapy. Clinical signs are neither sensitive nor specific and systematic screen for deep vein thrombosis in elderly patients could be justified using noninvasive techniques such as echo-Doppler or assay of D-Dimers. The aim of this study was to determine the prevalence of venous thrombosis diagnosed by echo-Doppler screening in a population of institutionalized elderly subjects. The frequency of risk factors and the cost of screening and subsequent health care were also evaluated. This study included 96 patients who underwent systematic echo-Doppler measurements. Clinical, biological and echographic data were recorded on individual file-cards for analysis. The prevalence of deep vein thrombosis diagnosis was 13.5% (13/96). All the deep vein thromboses discovered were in the popliteal area. No high risk group was found and there was found and there was no significant link with clinical signs or the level of D-Dimers. The cost of diagnosis and treatment in the particular conditions of our study were 5000 and 10,700 FRF respectively for each deep vein thrombosis diagnosed. The cost of diagnostic screening and treatment should be considered in light of the life expectancy and quality of life in this population. Thus in elderly institutionalized subjects, it would appear not to be reasonable to undertake systematic screening for venous thrombosis using echo-Doppler or D-Dimer assay.

The thoracic outlet syndrome includes primary axillary-subclavian vein thrombosis. The subclavian vein is compressed in a narrowed costo-clavicular space during certain movements of the arm. The intermittent compression of the vein results in position-dependent symptoms often misinterpreted. When occlusion of the vein occurs, the diagnosis of deep venous thrombosis suffers no difficulty. Non invasive vascular diagnostic techniques are nowadays paramount. Treatment, medical and/or surgical (removal of the first rib), depends on the venous state of the upper extremity.

Our experience with 91 operated cases in 84 patients (47 men, 37 women) relates essentially to arterial diseases resulting from overloading and diabetic arteriopathy. Diagnosis of critical ischemia is easy in clinical conditions, but it is advisable to rely on universally recognized hemodynamic standards to define this condition. Ankle pressure should be less than 400 mmHg and the Doppler trace flat or barely perceptible. Patients in our series had a mean ankle pressure of 32.4 mmHg. Local examination can determine the extent of gangrene, whereas general examination detects numerous, often associated defects diabetes, coronary artery disease, rhythm disorders, arterial hypertension, etc. As far as possible, these defects are to be corrected before surgery. X-ray examination (M. Kasbarian) is frequently done in conjunction with conventional aorto-arteriography and digital angiography. The later technique allows arteries to be visualized which are not seen with the conventional technique. The x-ray examination will indicate whether revascularization is feasible, although it cannot show whether it will be efficient. In our series, opacification of the plantar arches was predictive neither of success nor failure. But do tests exist which can predict the success of a revascularization attempt? It would be necessary to be able to estimate ankle pressure after the operation, and several methods have tried to do this. TcPO2 would seem to be a good examination. The possibilities of nuclear magnetic resonance are being studied, and the results thus far are promising. Preoperative explorations are carried out in a different situation. Arteriography performed in the operating room is a simple act which can reveal a usable downstream bed not indicated in preoperative X-rays, although it provides no hemodynamic data. Measurement of peripheral resistances would appear to be a very good predictive examination. Flow measurements by infusion or electronic flowmeter also seem to be predictive for bypass results. Unfortunately, these measurements are at present not widely performed and the critical threshold is assessed differently. Given the difficulty of correctly estimating the value of these numerous methods, many surgeons, ourselves included, have chosen to revascularize patients whenever the upstream bed as evaluated by X-ray indicates the presence of at least one viable artery.

Six cases of megalodolichoartery (M. D. A.) or arteriomegaly are reported. The arteriographic characteristics of the condition are reviewed: abnormally dilated and tortuous arteries, frequently aneurysmal, sometimes the site of obstruction by obliterative arteriosclerosis or embolism. Although clinically the relation between M. D. A. and arterial atheroma appears close, underlying abnormalities of elastic tissue cannot be excluded from the aetiology of the disease.

The authors report a case of severe ischaemia following an injection of sclerosant for varicose veins in the legs and discuss the pathophysiology of this accident. It seems that such an accident requires the immediate injection of a massive dose of cortisone; an intravenous infusion containing 400 mg of hydrocortisone hemisuccinate, 400 mg of heparin, 400 mg of Praxilene and 4 ampoules of injectable Tranxene 50; admission to a competent unit, i.e. with experience of this type of accident and the techniques of haemodilution combined with steroid therapy and the use of calcium inhibitors, for example Aldalate, as peripheral antispasmodics. Finally, the authors discuss the precautions which need to be taken in order to avoid such accidents, even in the hands of experts.

We have evaluated the therapeutic effect of the calcium entry blocking agent nifedipine in Raynaud's phenomenon associated with connective tissue diseases and in idiopathic digital vasospasm. In a preliminary study 16 patients with a digital vasospasm that could be induced by hand-immersion in cold water (4 degrees C) were challenged a second time with cold water 1 and 6h after 20 mg oral nifedipine. Nifedipine provided an effective protection against this cold-induced vasospasm in 14 of the 16 patients. Thirty patients were included in a short-term ambulatory study: Raynaud's phenomenon was associated with progressive systemic sclerosis (PSS) in 10 patients, systemic lupus erythematosus (SLE) in five and rheumatoid arthritis (RA) in three; it was idiopathic (I) in 12 patients. Each patient received, in a double-blind manner and random order, on two consecutive weeks, nifedipine (20 mg three times daily) and placebo. Nifedipine proved to be effective: the mean number of digital vasospastic attacks per week decreased from 27.3 to 5.8 (P less than 0.01). The results in the SLE and RA groups were similar and were pooled. The improvement (in % decrease) was better in the idiopathic group (90.9) than in the SLE and RA group (78.6, P less than 0.02) and the PSS group (64.0, P less than 0.01).

Results of vascular radiology and isotope examinations were compared in 48 patients with suspected ileocaval lesions (37 cases) or affections of the veins of the upper limb or superior vena cava (11 cases). Isotopic examination, which can be performed in ambulatory patients, respects normal hemodynamic conditions, is painless, and can be repeated, was found to give valid results, positive correlations with radiological investigation findings being present in 43 cases. Lack of correlation in the remaining 5 patients could have resulted from the period of time elapsed between the two examinations or the techniques employed during each investigation.

The author discusses the choice between medical or surgical treatment of a stage II arteriopathy of the lower limbs. 1. Medical treatment: recommended walking, prescription of calcium antagonists (Nifedipine and Diltiazem), maintenance of the cardiac blood flow and anticoagulant treatment. 2. Surgical treatment is less usual and should take into account the coronary involvement.

The frequency with which pulmonary embolism remains unrecognized clinically is well known and explains the value of pulmonary scintigraphy when there is the slightest suspicion of pulmonary embolism or in cases of unexplained dyspnoea of effort after a standard cardiac and pleuro-pulmonary examination. The practical value of a regular pre-operative electrocardiogram and of anticoagulant treatment during the acute phase of myocardial infarction are emphasized. Certain precautions to be observed during the use of antivitamins K in cases of heart failure are outlined.

Persistence of an embryonic hypoglossal artery, discovered during exploration of an atheromatous carotid artery stenosis, is a rarely observed anomaly that results from an embryologic slip during closure of basilo-carotid communications. Encephalic protection must be ensured during treatment of such lesions, and the establishment of a shunt during operation has to be considered.

Erythromelalgia is a vascular acrosyndrome affecting mainly the feet and triggered by elevation of room temperature. It may be primary, or secondary, in particular to a polycythemia, when an increased platelet count plays an essential role, explaining the beneficial effect of aspirin or NSAI agents that inhibit platelet prostaglandin cyclo-oxygenase. The favorable action of beta-blockers could result from the possible existence of an anomaly of cutaneous adrenergic nerves.

In each of the 16 patients included in our first study [6 idiopathic Raynaud's phenomenon (I), 4 associated with systemic lupus erythematosus (SLE) and 6 with progressive systemic sclerosis (PSS)] digital vasospasm could be reproduced by immersion of both hands in cold water (4 degree C). Each patient received in a double-blind manner and random order on two consecutive days, the calcium-channel blocking agent nifedipine (20 mg) and placebo. Nifedipine protection against vasospasm provoked by cold water (4 degrees C) was considered good or excellent in 14 of the 16 patients (p less than 0.001 versus placebo). In the second study, 30 patients [12 I, 10 PSS, 5 SLE and 3 rheumatoid arthritis (RA)] received in a double blind manner and random order, on two consecutive weeks, nifedipine (20 mg 3 time daily) and placebo. The improvement with nifedipine (in percentage of the decrease of the number of vasospastic attacks) was 90.95 in the 1 group, 78.63 SLE and RA and 64.02 in PSS (p less than 0.01). An open study during 3 months has confirmed the effectiveness of nifedipine (10 mg 3 times daily). The improvement was 88.92 in the 1 group, 76.33 in SLE and RA and 59.16 in PSS, 7 out of 30 patients stopped the treatment because of side effects (headache, flush, nausea, oedema of the ankles). Thus nifedipine appears to be extremely useful in the treatment of Raynaud's phenomenon.

The most frequent cause of acute ischaemia of the lower limbs is arterial: thrombotic, embolic and spastic. In cases of arterial embolism, the site of origin is the left side of the heart in 9 cases out of 10: ischaemic heart disease in 2/3 of cases, with atrial fibrillation (A.F.) in 50% of cases, rheumatic valvular disease with A.F. in 1/5 of cases and more rarely, idiopathic A.F., auricular disease and cardiomyopathies. Arterial emboli can be fragments from a wall thrombus (aortic or arterial aneurysm), or atheromatous material from an ulcerated plaque. In 11% of cases the origin of the embolus is never found. Arterial thrombosis is due to chronic vascular disease in 1/3 of cases, popliteal aneurysm and thromboangiitis obliterans. The iatrogenic causes are rare: use of the arterial route, and arterial prosthesis, accidental intra-arterial injection during sclerotherapy for varicose veins. Arterial spasm is seen in cases of phlegmatia caerulea dolens. It ben be iatrogenic (ergotamine tartrate, dihydroergotamine, methysergide), toxic (L.S.D.) or spontaneous.

The respective roles of thrombosis and spasm in the pathogenesis of coronary disease is a subject of current discussion. Critical study of trials of long-term secondary prevention of myocardial infarction carried out between 1967 and 1982 have failed to yield any definitive conclusion as to the value of oral anticoagulants, aspirin, sulfinpyrazone or dipyridamole. However oral anticoagulants should be prescribed in the long-term, in the absence of any contra-indication, in cases of myocardial infarction complicated by ventricular ectasia, arrhythmias or cardiac failure with cardiomegaly. The use of better methods in secondary prevention trials would be desirable. Primary prevention of myocardial infarction using drugs raises difficult problems, in particular economic.

We have evaluated the therapeutic effect of the calcium-channel blocking agent nifedipine in Raynaud's phenomenon associated with connective tissue diseases and in idiopathic digital vasospasm. Thirty patients were included in this study: Raynaud's phenomenon was associated with progressive systemic sclerosis (PSS) in ten patients, systemic lupus erythematosus (SLE) in five and rheumatoid arthritis (RA) in three; it was idiopathic (I) in twelve patients. Each patient received, in a double-blind manner and random order, on two consecutive weeks, nifedipine (20 mg three times daily) and placebo. Nifedipine proved to be effective: the mean number of digital vasospastic attacks per week decreased from 20.30 to 5.83 (p less than 0.01). The results in the SLE and RA groups were similar and were pooled. The improvement (in percent decrease) was better in the idiopathic group (90.95) than in the SLE and RA group (78.63, p less than 0.02) and the PSS group (64.02, p less than 0.01).