Experimental study of transductal dissemination of cancer of the pancreas

Experimental studies on the mechanims of transductal dissemination of the pancreas carcinoma was made in rabbit by injection of VX2 carcinoma suspension into the pancreatic duct. Ductal occlusion was conductive to nidation and growth in the pancreas of intraductal floating cancer cells, but tumor growth also occured in 40% of animals in which the duct was not occluded. The mechanisms of nidation in the pancreas of intraductal floating cancer cells were direct embedding into the ductal wall, and leakage of cancer cells from the duct in the process of pancreatic fibrosis due to ductal obstruction. Expansive tumor growth in the pancreas was more vigorous the smaller the degree of fibrosis of the pancreas, and was most active where associated acute pancreatitis was seen or where the pancreas was X-irradiated one week before injection of carcinoma suspension.

Studies of the growth and infiltration of experimental tumor of the pancreas in rabbits

An experimentally transplanted pancreatic cancer was induced by means of an intraductal injection of Vx2 carcinoma supernatant into the pancreatic duct of rabbits. The presence of ductal obstruction appeared to assist the nidation and growth of injected cancer cells in the pancreas. Tumors induced in the head of the pancreas grew by extension to the body and tail where they also produced interspersed, nodular tumor masses. Tumors induced in the body and tail region, on the other hand, grew by direct expansion towards the head, but this did not produce the interspersed nodular tumors in the head portion. These observations indicate that cancer of the head of the pancreas associated with the stenosis or obstruction of the pancreatic duct resulted in ductal dissemination and extensive lymphatic infiltration in the body and tail, a wider cancer invasion than recognizable at the gross cancer border. This extension was noncontinuous and interspersed, so that radical curative surgery for such cancer of the head of the pancreas would indicate total pancreatectomy.

Relations between occlusal interference and jaw muscle activities in response to changes in head position

The jaw muscles responded to changes in the head position. Electromyographic responses to head positions were classified as either of two types--balanced and unbalanced. The balanced type of electromyographic responses of participants with normal occlusion changed to the unbalanced type after being set with an overlay to make a premature contact artificially, and returned to the balanced type after removal of the overlay. The unbalanced type of electromyographic response of participants with occlusal interference turned to the balanced type after occlusal adjustment.

Fabry's disease on the mechanism of the peripheral nerve involvement

A sural nerve biopsy of a patient with Fabry's disease showed depletion of larger myelinated fibres, but smaller myelinated and unmyelinated fibres were intact. Epineurial and to a lesser degree endoneurial vessels revealed abundant lamellar inclusions in the endothelial and perithelial cells. Larger myelinated nerve fibres contained glycogen granules in the vacuoles caused by splitting of the adaxonal membranes. A skin biopsy revealed abundant inclusions in the secretory cells and myoepithelial cells of the sweat glands. The lumen of the gland was packed with inclusions like those in the vessel walls. The pain and anhydrosis might be caused by accumulation of glycolipid in the vasa nervorum and sweat glands and not by autonomic nerve involvement.

Dengue virus plaque formation on microplate cultures and its application to virus neutralization (38564)

Dengue virus plaque formation on BHK-21 cell microplate cultures was described. The clear plaques were visible usually 5 days after incubation in a CO-2 incubator at 37 degrees. The cells cultured in a 3-oz bottle were sufficient to prepare two microculture plates which were usually ready for use after 1-2 days of cultivation in the CO-2 incubator at 37 degrees. The overall procedures were easy and of economic advantage.