Showing papers by "Northampton Community College published in 1969"

Reconstruction of lateral ligament tears of the ankle. An experimental study and clinical evaluation of seven patients treated by a new modification of the Elmslie procedure.

Abstract: Experimental cadaver studies showed that Elmslie type of repair for rupture of the anterior and interior lateral ligaments of the ankle and subtalar joints is more effective that other procedures. A new modification of the Elmslie operation is described. It has been used successfully on seven patients followed for over two years. The procedure is simple and effective, although it does cause limitation of foot inversion amounting to 15 to 30 degrees.

Subluxation of the distal radio-ulnar joint by hyperpronation.

Abstract: 1. Six cases of subluxation of the distal radio-ulnar joint by a probable hyperpronation injury are described. In five of the six patients, there is an unusual type of trauma producing the injury; and, in the sixth patient, the presence of severe neuromuscular disease is noted. 2. The injury is a rotatory subluxation of the distal end of the radius on the ulna without evidence of rupture of the dorsal and volar radiocarpal ligaments or the triangular cartilage. 3. The characteristic roentgenographic sign is apparent shifting of the ulnar styloid process laterally when roentgenograms are made in pronation. 4. Possible errors in the making of the roentgenograms at the time of injury are described. 5. Follow-up examination of an untreated injury showed definite disability in the wrist one and a half years later with some limitations of motion. 6. Treatment by closed reduction and immobilization in supination is recommended. 7. An additional case is presented of a three-year-old child who showed all the clinical findings but, because of the lack of ossification in the distal ulnar epiphysis, the roentgenographic diagnosis could not be made.

The chemical reactions of the haemagglutinins and neuraminidases of different strains of influenza viruses. I. Effect of reagents reacting with amino acids in the active centres.

Abstract: Studies of the chemical reactions of the haemagglutinins and neuraminidases of eight strains of influenza viruses have been made by the use of chemical reagents reacting with chemically active groups in the protein molecule. The results indicate a close resemblance between the active centres of the haemagglutinins and neuraminidases in all the strains tested. In all cases the activities were unaffected by reagents reacting with the —SH group of cysteine, the —CH 3 S group of methionine, the amino group of lysine, the guanidyl group of arginine, or the indole ring of tryptophan. In all cases both the haemagglutinating and enzymic activities were reduced or destroyed by agents reacting with amide groups or reacting with both tyrosine and histidine. By the use of iodine under conditions in which tyrosine reacts but not histidine, and fluorodinitrobenzene under conditions in which histidine reacts more strongly than tyrosine, it was possible to detect a number of different active centres. (1) An active centre containing histidine and an amide group but not containing tyrosine was present in all the virus strains and was the only centre detectable in A 1 and A 2 strains. This type of centre appeared to possess both haemagglutinating and neuraminidase activity. (2) Active centres containing tyrosine and an amide group were detected in strains of A and B viruses. There was some evidence suggesting that tyrosine-containing centres were of two types: one possessing both haemagglutinating and enzymic activity while the other was a haemagglutinin without neuraminidase activity. The results could be explained by supposing that the presence of histidine in the active centre was essential for neuraminidase activity and that enzymically active tyrosine-containing centres also contained histidine, but that tyrosine could substitute for histidine, but that tyrosine could substitute for histidine in haemagglutinating centres.

Actuating assemblies and components therefor particularly suitable for electrical switches

Abstract: A switch assembly comprises an actuating member and a biasing assembly movable along a common longitudinal axis. Initial movement of the actuating member causes deformation of the biasing assembly thereby to energize the same. A position is reached where the biasing assembly moves towards a less stressed condition, such movement being adapted to actuate the device provided with the actuating assembly.

The chemical reactions of the haemagglutinins and neuraminidases of different strains of influenza viruses. II. Effects of reagents modifying the higher order structure of the protein molecule.

Abstract: The results of treatment of influenza virus strains with chemical reagents acting on the higher-order structure of protein molecules shows that both the haemagglutinating and enzymic activities are susceptible to these agents but there are considerable differences between the different strains and the neuraminidase activity is more sensitive than the haemagglutinating activity.The neuraminidase activity of A and A1 strains is destroyed by urea, guanidine, urea+dithiothreitol and mercuric chloride. The haemagglutinin of the PR 8 and SWINE strains is resistant to urea and mercuric chloride but destroyed by guanidine and by urea+dithiothreitol. The haemagglutinin of the DSP strain of virus A and the A1 strains is resistant to urea, guanidine and mercuric chloride but is destroyed by urea+dithiothreitol.The neuraminidase activity of the A2 strains is more resistant than that of the A and A1 strains. It is resistant to mercuric chloride and partially resistant to urea but is destroyed by guanidine and by urea+dithiothreitol. The A2 haemagglutinin is resistant to urea, urea+dithiothreitol, and mercuric chloride but is destroyed by guanidine.The LEE virus neuraminidase is resistant to urea and partially resistant to guanidine but is destroyed by urea+dithiothreitol and mercuric chloride. The LEE haemagglutinin is resistant to urea, guanidine and mercuric chloride but is destroyed by urea+dithiothreitol.It is suggested that the surface projections of the virus particle are protein polymers each made up of three or four monomers which are the components of the V antigen complex. Antigenic activity is a function of the primary or secondary structure of the monomers, haemagglutinin activity is a function of the tertiary structure of the monomers, while neuraminidase activity is a function of the quaternary structure of the polymer.From studies of the chemical reactions of their haemagglutinins and neuraminidases strains of influenza virus A can be classified into groups. These groups are very similar to but not precisely identical with groupings made by serological methods.

Pulmonary embolization following inferior vena caval interruption.

Abstract: Presented before the Tenth Annual Meeting of the International College of Angiology, Geneva, Switzerland, July 23-28, 1968. Pulmonary embolization following vena caval interruption secondary to deep leg or pelvic thrombophlebitis has recently become a somewhat controversial subject which can present a rather perplexing problem as to diagnosis and effective management. There are several definite indications for such a procedure. The first, and certainly the most common in the literature, is &dquo;failure of anticoagulant therapy.&dquo; Unfortunately, there is rarely any definite description in the literature of exactly what type of anticoagulant therapy failed. Another indication is, of course, any embolic situation in which there is a contraindication to anticoagulant therapy, such as a bleeding peptic ulcer, a recent cardiovascu-