Document 0JqZjm83erDvwrg9eqDDRrm7m

/ (0$ @) 7=3 fa & 0=0 Industrial Hygiene Digest April. 19b samples were taken at 13 points around the quarries. A second survey was made between June 25 --November 29, 1963. The results of these surveys are presented and are avail able upon request. 394 Certain ImmunobloloBical Shifts in Asbestosls. F. M. Kogan, A. A. Gerasimenko, and C. I. Bunimovich. Gigiena i Sanit. 30, 34-40 (May, 1965). Russian. Long-term inhalation of asbestos dust brought about a fall of the immunobiological rea-ctivi of the body and, probably, its allergic responses. There was a most distinct inhibition of complement titer. The changes of the complement titer preceded the onset of clinical and x-ray symptoms of pneumoconiosis. The study of the immunobiological reactivity of pxersi sick with asbestosis, caused by the inhalation of chrysotile-asbestos and anthophyllite -- asb showed that in the first case the reactivity was inhibited to a greater extent, This was not< in the clinical course of asbestosis as well. Persons sick with asbestosis and those work under conditions of high dust content of the air presented lesions peculiar to auto-immunoli disease: rise.in the alpha-globulin content and anti-complement activity of the serum. -- APCA -Abet 395 Electron Microscope Studies of Asbestos in Man and Animals. J.M.G. Davis. Med. lavoro 56, 521-529 (June-July 1965). In both guinea pig and human lung material the formation of asbestos bodies has been stuowr. to be an intracellular process. The/irst sign of asbestos body formation is the accumulatl of dense granules approximately 60 A in diameter around the asbestos fiber. It is suggest that these granules represent ferritin material. Usually the asbestos body coating consist) of a single dense layer of ferritin, but often a whole series of layers of varying density is present. The outermost zone of these bodies often consists of an irregular layer of radiall arranged fibrous material but occasionally the whole body coat consists of these fibers whii have a diameter of 50-60 A . From the evidence of this study it would appear that the >well known segmentation of asbestos bodies can be of two types. In one the segmented appenran is due to the deposition of the body coating in separate globules, and in the other it is due ti the splitting of a previously smooth coat. APCA A.bst PHYSICAL ASPECTS OF THE ENVIRONMENT I 396 Recent Findings in the Pathogenesis of Decompression Slckneas (Dysbarlsm). A. T. K. Cockett, R. M. Nakamura, andJ.J. Franks, Surgery 58, 384-389 (Aug. 1965). A recent review of human decompression sickness pointed out that one-third of the reposted cases suffered from hemoconcentration. This prompted the authors to document this ap parent loss of plasma volume by measuring intravascular fluid shifts in experimental anlma before and after decompression. Mongrel dogs were used as experimental animals. Af'-ter suitable catheters had been placed in the animals, they were placed in the overcompress ion decompression chamber and were overcompressed to six atmospheres absolute. The in.ere; in barometric pressure was seven pounds (psi) per minute. After a stabilization period o 60 minutes the animals were decompressed at a rate of seven pounds (pal) per minute. *The plasma volume decreased from four to 38?) up to 5-1/2 hours after removal of seven dog s from the decompression chamber. The role of the bubble formation with progressive re due in blood pressure is discussed in the slower deaths of ten animals. Bone marrow emboLl w< found on routine histologic sections of all the animals who were autopsied. Nevertheless , tl exact pathophysiologic mechanismof dysbarlsm remains obscure according to the authors . - Cond. from Am. Rev. Resp. Dis. Afcsets ; j I | 397 The Effect of Joint Action of Noise and Vibration on the Vibration Sensitivity of Adolescemls. A. I. Tsysar. Gigiena i Sanit. 3K), No, 6, 30-36 (1965). Russian. The authors studied the effect produced from work with electric and pneumatic instruments < the vibration sensitivity of adolescents and the extent of the noxious effect produced by va.rio parameters of vibration. The adolescents were highly sensitive to the action of noise aned vibration factors: a rise in the threshold value of the vibration sensitivity was noted in ejaae of a comparably short service record and a short term of work with the instruments. In the course of a work day, changes of the vibration sensitivity occurred mainly in Insignificant and moderate rises of its threshold values, which are evidently connected with changes ixt th functional state of the vibration analyzer. -- Public Health Eng. Absts 21. 03122108