Search

We studied the effects of rheumatoid factor (RF) on binding of immune complexes to activated C3 (C3b) receptors in vitro. IgM fraction of serum containing RF activity (IgM-RF), IgM isolated from pooled normal human serum and having no RF activity (IgM-control), bovine serum albumin, and Veronal buffered saline solutions were used in a C3b assay system consisting of aggregated human IgG (AggHuIgG) coupled to sheep erythrocytes (SRBC) with guinea pig and normal human serum complement. The number of glomerular bound AggHuIgG-SRBC with IgM-control and bovine serum albumin or Veronal buffered saline was similar, while the number of bound cells with IgM-RF was reduced significantly. This effect was seen with both guinea pig and normal human serum complements. Supernatant hemolytic complement activity was maintained with IgM-RF, but reduced with control solutions. The blocking factor was shown to be RF by serial dilutions of IgM-RF resulting in inverse correlations with latex flocculation and inhibition of SRBC binding, absorption of blocking from IgM-RF with insolubilized AggHuIgG, and failure of IgM-control to block binding. IgM-RF did not directly interfere with activation of complement, but blocked attachment of C3 to AggHuIgG and formation of C3b capable of reacting with glomerular receptors. These results showed that IgM-RF can inhibit binding of AggHuIgG complexes to human glomeruli. This in vitro phenomenon may represent a possible protective mechanism of RF in vivo in diseases with immune complexes.

Study of chemical sympathectomy in endotoxin-induced lethality and fibrin deposition. Shock and the generalized Shwartzman reaction are well known features of endotoxin which have been shown to involve the sympathetic nervous system. The mechanism of sympathetic nervous system involvement with endotoxin injection was studied in rabbits chemically sympathectomized with 6-hydroxydopamine. Endotoxin, in doses producing a spectrum of morbidity and mortality in normal rabbits, was administered i.v. to chemically sympathectomized, normal, and unilateral renal surgically sympathectomized animals. Chemical sympathectomy produced a significant depletion of tissue norepinephrine which, in endotoxin recipient animals, was associated with a significantly lower mortality rate and greatly decreased fibrin deposition in the lungs and kidneys, despite intravascular coagulation. Unilateral renal sympathectomy afforded protection to the ipsilateral kidney, but data on mortality and systemic fibrin deposition were similar to those reported for normal rabbits given endotoxin. Six-hydroxydopamine prevents significant tissue injury secondary to endotoxin in this experimental model. In addition, the data provide direct evidence that an intact reactive sympathetic nervous system is essential for development of lethal toxicity and generalized Shwartzman reaction due to endotoxin. Etude de la sympathectomie chimique de la lethalite et des depots de fibrine chez animaux qui ont recu l'endotoxine. Le choc et le phenomene de Schwartzman generalise sont des consequences bien connues de l'endotoxine et il a ete montre que ces reactions impliquent le systeme nerveux sympathique. Le mecanisme de la mise en jeu du systeme nerveux sympathique par l'injection d'endotoxine a ete etudie chez des lapins ayant subi une sympathectomie chimique par la 6-hydroxydopamine. L'endotoxine, aux doses qui determinent une morbidite et une mortalite chez les lapins normaux, a ete administree par voie intraveineuse a des animaux normaux, ayant subi une sympathectomie chimique ou ayant subi une sympathectomie renale, chirurgicale et unilaterale. La sympathectomie chimique a produit une depletion significative de norepinephrine tissulaire qui, chez les animaux qui ont recu l'endotoxine, a ete associee a une diminution significative de la mortalite et une diminution importante des depots de fibrine dans les poumons et les reins malgre la coagulation intravasculaire. La sympathectomie unilaterale a protege le rein ipsilateral mais la mortalite et les depots systemiques de fibrine ont ete semblables a ceux observes chez les lapins normaux qui ont recu l'endotoxine. La 6-hydroxydopamine diminue de facon significative les alterations tissulaires secondaires a l'endotoxine dans ce modele experimental. De surcroit, ces observations apportent la preuve directe de ce qu'un systeme nerveux sympathique intact et reactif est essentiel pour l'apparition de la lethalite et du phenomene de Schwartzman generalise consecutifs a l'endotoxine.

Two cases of transient paralysis of upper extremity after percutaneous cannulation of the subclavian vein for hemodialysis are presented for the first time. Large amounts of lidocaine used, together with its deep and too lateral administration are responsible for development of this transient complication.

The present report concerns a man with renal cortical necrosis. There was no apparent precipitating causative agent in this case. The renal pathologic findings of intravascular necrosis, occurring concommitant with an acute hemolytic anemia, characterized by the presence of the fragmented red blood cells of microangiopathic hemolytic anemia in the peripheral blood are similar to changes seen in children in the hemolytic-uremic syndrome (HUS). 1-8 An increasing number of adult patients with bilateral renal cortical necrosis associated with microangiopathic hemolytic anemia (so-called HUS of adults) are now being reported 9-16 ; however, most reports concern patients with predisposing diseases, such as obstetric complications. Patient Summary The patient is a 55-year-old black man who was admitted to the Boston City Hospital Fifth Surgical Service (Harvard) Jan 21,1970, with a four-day history of nausea, vomiting, malaise, general weakness, and anuria. No urine was obtained on urethral catheterization. His admission blood urea nitrogen (BUN)