Detection of circulating antigen-antibody complexes by their inhibitory effect on the agglutination of IgG-coated particles by rheumatioid factor of Clq

The agglutination of Ig-coated particles by human RF or Clq can be inhibited by Ig aggregates or AgAb complexes. The effect of Ig class was studied by means of agarose-linked human monoclonal Igs. RF was inhibited by all subclasses of IgG and IgA but not by IgM, whereas Clq reacted with IgM, IgG3 and IgG1. Heat-aggregated IgG3 was fractionated by gel-filtration on Ultrogel. Inhibition was restricted to certain fractions of aggregates, viz (IgG3) approximately 7 and (IgG3) approximately 21 for RF, and (IgG3) approximately 10, (IgG3) approximately 14 and (IgG3) approximately 27 for Clq. In a precipitin curve experiment, it was found that RF was inhibited by soluble complexes over an extended range of AgAb ratios, the inactivation of Clq being limited to complexes with 2-5 times antigen excess. Inhibiting factors were found in patients with various diseases and, at low titres, in 22% of healthy people. In 27% of patients' sera, the inhibitors were demonstrable by Clq only after removal of endogenous RF by adsorption on insolubilized IgG. In several patients endogenous agglutinating activity and direct inhibitory activity tended to alternate during the course of the disease. Sera from various patients were also filtrated on Ultrogel and the elution was monitored by immunoassay of IgA, IgM and IgG, as well as by the two inhibition tests. The inhibiting factors were distributed over several peaks which only partially coincided with the elution profiles of IgG and IgM.     

Transposition of the tendon of pronator teres in cerebral palsy

We have considered the indications for and results of transplanting pronator teres to extensor carpi radialis brevis in cerebral palsy. The operation has some virtue but a very limited application. We achieved satisfactory functional results in six of nine patients and some improvement in one. Two operations failed because of poor selection. In all patients the appearance of the limb was improved.     

Effects of maternity-stay legislation on 'drive-through deliveries'

We evaluate the change in length-of-stay and charges for vaginal and cesarean deliveries before and after the implementation of a law establishing a minimum maternity stay in Maryland. Using discharge abstract data collected by the Maryland Health Services Cost Review Commission, we find that after the law was enacted, Maryland's average length-of-stay and average charges for both types of deliveries increased, but the increase in charges was less than the cost of an average hospital day. Multivariate analysis shows that the implementation of the law reduced the sources of variation among mothers' length-of-stay and hospital charges. Overall, we estimate that the law cost payers an additional $5.5 million for maternity stays.     

Intraocular neoplastic cyst from mucoepidermoid carcinoma of the conjunctiva

An 89-year-old woman with recurrent conjunctival mucoepidermoid carcinoma developed intraocular inflammation and an elevated fundus lesion that simulated choroidal detachment in her affected right eye. Intraocular invasion of squamous cell carcinoma was suspected and the eye was enucleated. Pathologic examination of the enucleated eye showed intraocular invasion by conjunctival mucoepidermoid carcinoma that formed a suprauveal cyst lined with malignant epithelial cells. The patient developed an orbital recurrence 1 year later and underwent orbital exenteration. She died 2 years later from an unrelated cause. Conjunctival mucoepidermoid carcinoma can exhibit intraocular invasion and produce an intraocular neoplastic cyst.     

Survival after massive (>2000) Africanized honeybee stings

We report the clinical case of a man who survived a massive attack of Africanized bees (>2000 bee stings). The man experienced anaphylactic shock and multisystem organ failure (neurologic, hepatic, renal, and hematologic failure). He was treated with administration of dopamine hydrochloride, antihistaminic agents, corticosteroids, fluid and electrolyte replenishment, peritoneal dialysis, and plasmapheresis. No sequelae have been observed during follow-up.     

Metabotropic glutamate receptor-mediated inhibition and excitation of substantia nigra dopamine neurons

Microiontophoretic drug application and extracellular recording techniques were used to evaluate the effects of the selective metabotropic glutamate receptor (mGluR) agonist (1S,3R)-1-aminocyclopentane-1,3-dicarboxylate(1S,3R-ACPD) on dopamine (DA) neurons in the substantia nigra zona compacta (SNZC) of chloral hydrate-anesthetized rats. 1S,3R-ACPD had a biphasic effect on the firing rate of DA cells, initially decreasing, then increasing the firing rate. 1S,3R-ACPD also increased the burst-firing activity of DA neurons. Application of the ionotropic receptor (iGluR) agonists (R,S)-alpha-amino-3-hydroxy-5-methylisoxazole-4-propionic acid (AMPA) or N-methyl-D-aspartate (NMDA) increased the firing rates of neurons which had responded to 1S,3R-ACPD, indicating that mGluRs and iGluRs reside on the same neurons. The initial inhibitory period was not antagonized by systemic haloperidol or iontophoretic bicuculline, indicating a lack of DA or gamma-amino-n-butyric acid (GABA) involvement in this effect. Combined application of the AMPA antagonist, 2,3-dihydroxy-6-nitro-7-sulfamoylbenzo(f)quinoxaline (NBQX), and the NMDA antagonist, (I)-3-(2-carboxypiperazin-4-yl)propyl-1-phosphoric acid (CPP), at currents which antagonized AMPA and NMDA, did not antagonize either the inhibitory or excitatory effects of 1S,3R-ACPD. Application of the metabotropic antagonist (S)-4-carboxy-phenylglycine antagonized both the inhibitory and excitatory effects of 1S,3R-ACPD. These results indicate that mGluRs may play a role in the modulation of dopaminergic activity in the SNZC.     

Innovation in medical technology: reading the indicators

Investment in medical technology innovation has enabled significant advances in patient care. An understanding of the dimensions and measures of innovation is critical in fully assessing the implications of many policy initiatives under debate. This Data Watch presents several indicators of inputs and outputs associated with medical device innovation, including public- and private-sector research and development (R&D) investment, patent activity, product regulatory clearance patterns, and market acceptance trends. Changes in these selected indicators point to a potential shift occurring in both the nature of and the investors in the innovation process.