Histological study of the circulatory system of human dental pulp from individuals under local anesthesia and electro-acupuncture.

A transmission electron microscopic (TEM) study was conducted on dental pulp obtained from patients under acupuncture or infiltration local analgesia. It was difficult to differentiate lymphatic circulation in the dental pulp that received infiltration anesthesia, because the vessels were constricted, congested, and showed stasis and thrombosis. On the other hand, the dental pulp that received acupuncture showed normal arterioles, capillaries, and venules, as well as some lymph capillaries and small efferent lymphatic vessels that measured about 8 microns and 100 microns in diameter, respectively. The lymphatic endothelial walls had many intercellular gaps, an imperfect basal lamina, and a few discontinuous pericytes. Between the openings in the lymphatic vessels, there were bundles of junctional filaments extending towards the dental pulp connective tissue. Therefore, the lymphatic system, which contains mainly B-3-alpha capillaries, is a leaky tissue for regulating fluid in the dental pulp.

Are peripheral lymphatics damaged by high pressure manual massage?

Massage of the foot in men and the hindpaw in dogs was performed by applying external pressures of 70-100 mmHg for a period of one, three, five, and ten minutes with a frequency of 25 strokes per minute. This protocol was performed on individuals without edema, on dogs with experimental lymphedema and men with post-thrombotic venous edema. After ten minutes of forceful massage, focal damage of lymphatics was present. In a group of dogs with lymphedema and men with post-thrombotic venous edema, the alteration of lymphatics was greater than in normal individuals and evident only after 3 to 5 minutes of massage. At first, the forceful massage affected the endothelial lining of the initial lymphatics. Alterations of lymphatic collectors were visible later. The fluid in lymphedema was translocated by massage using high pressure from the interstitium into the lumen of lymphatics by means of the open junctions and by artificial cracks that develop from injury to the lymphatic wall. Vigorous massage in lymphedema also produces loosening of subcutaneous connective tissue, formation of large tissue channels and release of lipid droplets that enter the lymphatics. By this mechanism, massage helps reduce the amount of fat cells in the lymphedematous leg.

[Electron microscopy observation on pre- and post-treatment skin of dorsum pedis of chyluric patient treated with heat-clearing and hemostatic drugs--the lymphangial wall damage being the pathogenesis of chyluria].

Heat-clearing and hemostatic drugs were effective in treating chyluria. In order to explore the curative mechanism, a group of 10 in-patients with chyluria were chosen and treated with heat-clearing and hemostatic drugs for 45 days. Some pre- and post-treatment skin from dorsum pedis of the patients were taken off and observed under electron microscope. It showed that the walls of lymphatic capillaries were seriously damaged before treatment and rehabilitated wall after treatment. The pinocytotic vesicles were packed tightly in the endothelial cells of capillaries before treatment and their number was decreased remarkably after treatment; the mast cells were rare in number and abnormal as spindle shape before treatment and they increased in number and became round or oval in shape, the nucleus became large, the granules they contained became more in number and larger in size after treatment, lymph edema was noticed before treatment and it disappeared after treatment. The result showed that the extensive lesion of lymphangial walls is the pathogenesis of chyluria, while the rehabilitation of them is the curative mechanism. It seems that in the process of rehabilitation the mast cells act took the role of "soldier-engineer".

Effects of the adjuvant DEAE-dextran and Staphylococcus aureus on the lymph pathways and filtering capacity of popliteal lymph nodes in sheep.

The effects of subcutaneous injections of the adjuvant DEAE-dextran and, or killed Staphylococcus aureus on the structure of the lymph pathways of popliteal lymph nodes in sheep were examined using light and electron microscopy and Microfil casts. Dextran with or without killed S aureus caused significant changes in the lymph pathways both within the node and outside it. However, killed S aureus alone did not. The changes included anastomoses among afferent lymph vessels and between afferent and efferent lymph vessels; proliferation of vessels around the node; joining of parts of the capsule and trabeculae to adjacent parenchyma with loss of parts of the subcapsular and trabecular sinuses; enlargement of medullary sinuses; and reduction of the number of reticular processes in sinuses throughout the node. These changes were accompanied by a reduced ability of the node to filter chicken red blood cells labelled with chromium-51 which were injected into an afferent lymph vessel.