Retinal vasculitis associated with autoantibodies to Sjögren's syndrome A antigen

Severe retinal vasculitis caused by a systemic lupus-like illness developed in two patients with distinctive clinical and immunologic characteristics. Both patients were young women with mild systemic disease and autoantibodies directed against a protein-ribonucleic acid complex termed the Sjögren's syndrome A antigen (SSA). One patient had no antibodies to nuclear antigens on conventional testing, and the other had a low-titer antinuclear antibody test. At the time of onset of retinal arteriolitis, neither patient had an exacerbation of multisystem disease or serologic activity. Despite oral and parenteral corticosteroids, cytotoxic agents, and panretinal photocoagulation, both patients suffered progressive irreversible retinal ischemia, optic disk and retinal neovascularization, vitreous hemorrhage traction retinal detachment, and anterior segment neovascularization.

Competition between antigen and anti-idiotypes for rheumatoid factors

Many idiotypic determinants on antibody molecules are thought to be located at the antigen binding site, and therefore the interaction between idiotype (Id) and anti-idiotype (anti-Id) is expected to be inhibited by the antigen. We describe two IgG and one IgM rheumatoid factors whose interactions with their respective anti-Id could only be partially inhibited by very large amounts of antigen, i.e., normal IgG. The anti-Id, however, readily inhibited the binding of their respective rheumatoid factors to IgG. The differences in interaction energies resulted in failure of antigen to readily block the Id-anti-Id interaction, and did not mean that the Id was not at the antigen combining site. The association constants for the Id-anti-Id interactions varied from 1.3 to 14.8 X 10(7) M-1, whereas the strength of the rheumatoid factor antigen bond is on the order of 10(5) M-1 for interaction with monomeric IgG. In addition, the anti-Id were able to remove rheumatoid factors that were bound to solid phase IgG, indicating that anti-Id have the potential for disrupting the immune complexes formed by antigen and antibody.

Competition between antigen and anti-idiotypes for rheumatoid factors

Many idiotypic determinants on antibody molecules are thought to be located at the antigen binding site, and therefore the interaction between idiotype (Id) and anti-idiotype (anti-Id) is expected to be inhibited by the antigen. We describe two IgG and one IgM rheumatoid factors whose interactions with their respective anti-Id could only be partially inhibited by very large amounts of antigen, i.e., normal IgG. The anti-Id, however, readily inhibited the binding of their respective rheumatoid factors to IgG. The differences in interaction energies resulted in failure of antigen to readily block the Id-anti-Id interaction, and did not mean that the Id was not at the antigen combining site. The association constants for the Id-anti-Id interactions varied from 1.3 to 14.8 X 10(7) M-1, whereas the strength of the rheumatoid factor antigen bond is on the order of 10(5) M-1 for interaction with monomeric IgG. In addition, the anti-Id were able to remove rheumatoid factors that were bound to solid phase IgG, indicating that anti-Id have the potential for disrupting the immune complexes formed by antigen and antibody.

Reflux esophagitis: an update

In recent years, much has been learned about the pathogenesis, diagnosis, and treatment of gastroesophageal (GE) reflux disease. Mucosal resistance, gastric contents, esophageal acid clearance, gastric emptying, and incompetency of the lower esophageal sphincter are contributing factors to GE reflux. Use of the various diagnostic tests and an overview of current therapy are summarized.

Esophageal contraction pressures are not affected by normal menstrual cycles

Previous studies of lower esophageal sphincter pressures during the menstrual cycle and pregnancy have suggested that the smooth muscle relaxing effect of progesterone depresses sphincter tone. Results, however, have been contradictory and limited to a small number of patients. We studied lower esophageal sphincter and distal peristaltic pressures during the follicular (days 2-8) and luteal (days 20-28) phases of the menstrual cycle. Twenty normal menstruating women (mean age 31 yr) not using oral contraceptives were evaluated. A low compliance pneumohydraulic infusion system was used for all studies. Lower esophageal sphincter pressure was determined by both rapid and station pull-through techniques. Distal peristaltic pressures were recorded 2 and 7 cm above the sphincter in response to 10 wet swallows (5 cc of H2O). Mean amplitude and duration in the distal esophagus were evaluated. Plasma progesterone and estrogen concentrations were obtained and correlated with changes in esophageal pressures. The results were as follows: (a) unlike prior investigations, we found the menstrual cycle had no effect on lower esophageal sphincter pressure and (b) likewise, no change in esophageal contractions in the distal esophagus was found during the cycle. We concluded that changes in female sex hormone concentrations that characterize the menstrual cycle are not associated with changes in parameters of esophageal motor function.

Morphine antagonists and consummatory behaviors

Opiate antagonists were tested for their effects upon either drinking or eating in eight experiments. Naloxone, nalorphine, and the active isomer of WIN 44,441 all reduce drinking. Neither an analog of nalorphine that does not cross the blood-brain barrier, nor the inactive isomer of WIN 44,441 is effective in reducing water intake. These data provide support for the conclusion that these antagonists ahve stereospecific effects within the central nervous system. Naloxone suppresses drinking following procedures inducing osmotic, volemic, or hormonal thirst. Naloxone suppresses eating following procedures inducing glucoprivation but does not alter eating elicited by tail-pressure. Collectively, these data lead to the conclusion that endorphins play a role in the organization of ingestive behavior following challenges to homeostasis.

A technique for estimating the position of the oxygen-hemoglobin dissociation curve

A nomogram was constructed which allows estimation of the P(50) value from the Po(2) and per cent O(2) saturation of a single venous blood sample. There was excellent correlation between 50 estimated P(50) values obtained in 27 severely ill patients when compared with P(50) values determined from constructed OH-DC's (correlation coefficient 0.92). The mean of the differences between the estimated and determined P(50) values was 1.5 mm Hg with a standard deviation of +/-1.1, and the maximum difference was 4 mm Hg.

Sediment Movement on the Continental Shelf near Washington and Oregon

The nuclides zinc-65 and cobalt-60 associated with river-borne particulate matter are incorporated in sediment on the Continental Shelf near the Colum- ia River. Changes in the relative concentrations of zinc-65 and cobalt-60 and in the ratio of the activity of zinc-65 and cobalt-60 suggest that radioactive sediment moves northward 12 to 30 kilometers per year along the shelf and 2.5 to 10 kilometers per year westward away from the coast.