Nencki

NENCKI, Marceli Wilhelmovich (1847-1901), an outstanding biochemist; born in Poland in the former Kalisz province. Due to his participation in the Polish uprising in 1863, he was forced to emigrate abroad. In 1870, he received the degree of Doctor of Medicine at the University of Berlin. From 1871, Nencki was an assistant at the Department of Pathological Anatomy in Bern, then a privat-docent; from 1876, a professor at the newly opened Department of Physiological Chemistry at the University of Bern; from 1888, he lectured on bacteriology. In 1891, Nencki took the position of head of the Chemical Department at the just-opened Institute of Experimental Medicine in St. Petersburg. Nencki's main works relate to the fields of organic and biological chemistry and bacteriology. His research concerning the structure of the coloring matter of blood is fundamental in this area. He discovered indole and must be considered the first to have synthesized indigo synthetically. Nencki's works on the question of urea formation, on oxidation processes in animal bodies, and on putrefaction and fermentation processes in the intestine are of great importance. He obtained salol, which found wide therapeutic application. Nencki also devoted much attention to questions of a practical nature; these include his works on antisepsis, disinfection, and the fight against cattle plague, etc. All of Nencki's works and the most important works of his students were published in two large volumes (Marceli Nencki Opera Omnia, Gesammelte Arbeiten von M. Nencki, 1869-1901, Bande I-II, Braunschweig, 1904) with an appendix containing a list of Nencki's biographies and obituaries dedicated to him. NEOARTHROSIS, or neoarthrosis (neoarthrosis) {from Greek neos-new and arthron-joint), a new joint in an unusual place, formed as a result of the displacement of the articular head from the articular socket in a dislocation {traumatic, congenital, or pathological). The formation of mobility at the site of non-united bone fragments after fractures should be referred to as false joints (see). Neoarthrosis is a formation functionally deficient, anatomically resembling a normal joint only in some of its components. Neoarthrosis is most often formed in irreducible, so-called old dislocations (luxatio inveterata), in ball-and-socket joints - the shoulder and hip. In an irreducible dislocation, after the disappearance of the hematoma, the weakening of muscular retraction, and the reduction of pain, the victim begins to gradually use the affected limb, adapting to the abnormal relationships in the area of the dislocated bone. Along with the development of movements, new anatomical relationships corresponding to the new functional conditions are recreated. In an irreducible dislocation of the hip joint, on the ilium, due to prolonged irritation by the articular head, the periosteum and connective tissue grow, and a hollow depression is formed, surrounded by a low ridge and more or less corresponding to the articular end of the dislocated bone. In the future, under the influence of frequent movements, the newly formed depression is polished; the surrounding connective tissue may form a kind of capsule. Such a neoarthrosis sometimes gives satisfactory function, which improves with prolonged exercise. Satisfactory function and only partial limitation of movements are given by neoarthroses in congenital dislocation of the hip joint, where the formation of a neoarthrosis completes the complex process of head displacement (see Dislocations, congenital dislocations). The displaced upward head stretches the articular capsule, which, due to prolonged friction and pressure, fuses with the new depression, so the new joint preserves the true articular bag. In adults, the newly formed articular bag is quite deep, especially in unilateral dislocation, since in this case the pressure of the head on the ilium is stronger and more prolonged, and the more intense the pressure of the head on the periosteum, the more pronounced the productive inflammation and the more favorable the conditions for the formation of a good neoarthrosis. Rarely do neoarthroses occur in pathological dislocations: here, usually in the area of the displaced articular head, movements in a noticeable, functionally effective volume are not restored.