Search PubMed⌕ Search

Biomedical subjects

M A Baron

Publications and source records attributed to M A Baron.

30 records · Page 2Linked to original sources
PubMed1977

[Role of serum fibrinogen penetrating the subarachnoid space in the pathogenesis of brief cerebral arteriospasm].

A mixture of fibrinogen (4 ml in a 1 per cent solutions) and thrombin (10 I.U.) were instilled into the cisterma magna of 18 dogs which led to the formation of a fibrin clot in the subarachnoid space. This fibrin clot produced a spasm of the large cerebral arteries, which resulted in a narrowing to 84.8 +/- 1.8 per cent of the initial value. The subsequent administration of 400 units of fibrinolysin into the cisterna magna led to the dissolution of the fibrin clot and the dilatation of the arterie to 116.3 +/- 2.5 per cent of the initial value. Experiments carried out in 15 cats showed that, after being brought in the subarachnoid space, the spasmogenic factor of the clot, which consisted of all blood components, passes through the arachnoid into the subdural space. The penetration of the spasmogenic factor from the blood clot located on the surface of the arachnoid from the subdural to the subrarachnoid space was not observed. The arachnoid proves to be a membrane which can only be passed in one direction by the spasmogenic blood factor.

Animals↗
PubMed1976

[Cerebrospinal fluid bearing channels of the pia meter].

The pia mater of the human brain hemispheres has liquor canals which form a continuous network communicating with the cisterns of the brain base. The wall of the liquor canals is formed by a fibro-collagenous framework covered from two sides with the arachnoidendothelium. In the canal walls there are openings, through which the lumens of the canals communicate with the lumens of alveoli. The liquor canals are divided into the circulatory and excretory ones. The circulatory canals are disposed in the depth of the cerebral sulci, the secretory canals--on the surface of the convolutions. The liquor moves along the circulatory canals from the cisterns of the brain base onto the surface of cerebral hemispheres. Excretory canals adjoin the arachnoid membrane which is part of its wall (the "roof"). In the "roof" of the liquor canals the fibrocollagenous basis and the number of layers of the arachnoid--endothelium are reduced, the intercellular spaces between the cells of the arachnoidendothelium are dilated. Through the roofs of the liquor canals the liquor is excreted from the subarachnoid space into the subdural space. Inside the liquor canals there are arteries of the pia mater hung up to the canal walls by trabeculae (cords) of a dense connective tissue.

Humans↗
PubMedDate not supplied

[Prolonged spasm of the arteries of the base of the brain during experimental fibrinolysis in the subarachnoid space].

An ex tempore mixture of fibrinogen (1%--4 ml) and 0.2 ml thrombin solutions forming a compact clot of fibrin in the subarachnoid space was introduced into the cisterna magna of dogs. To dissolve the fibrin clot 2 ml of a fibrinolysin solution with an activity of 400 units were introduced into the same cisterna 10--15 minutes thereafter. A total of 26 experiments were set up, of which 13 were served as controls with separate introduction of the mixture ingredients. Through serial vertebral angiography with a 50 per cent urotrast solution it was found that following introduction of the fibrinogen and thrombin mixture the lumen of the basilar artery and of its branches contracts on the average up to 89.2 +/- 1 per cent. After introduction of fibrinolysis the diameter of the artery initially increases up to 116.3 +/- 2.5 per cent. In 3 hours time a pronounced spasm of the basilar artery and of its branches is seen to develop up to 80.9 +/- 3.6 per cent and after 24 hours -- up to 73.9 +/- 2.1 per cent. The spasm persists for up to 10 days, but its intensity gradually declines. During subsequent 11--18 days the diameter of the brain base arteries returns back to normal. In control experiments no development of protracted spasm was demonstrated. Hence, it is established that the appearance of fibrinolysis products formed in the spinal fluid consequent upon dissolution of a clot of fibrin containing no blood cells is attended by the development of a protracted spasm involving major arteries of the brain.

Animals↗